Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting (Multiplication Rule): If an event $E$ can occur in $m$ ways and another independent event $F$ can occur in $n$ ways, then the total number of ways both events can occur together is $m \times n$.
There are 25 mathematics books and 24 physics books on a library shelf. In how many ways can we choose one mathematics and one physics book?
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting (Multiplication Rule): If an event $E$ can occur in $m$ ways and an independent event $F$ can occur in $n$ ways, then the total number of ways both events can occur together is $m \times n$.
A dice is a six-faced cube, with the faces reading 1, 2, 3, 4, 5 and 6. When two dices are thrown we add the digits they show on top and take that sum as the result of the throw. In how many different ways the first throw of the 2 dices shows a total of 5, and second throw of the 2 dices shows a total of 4?
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting (Multiplication Rule): If an event $E$ can occur in $m$ ways and an independent event $F$ can occur in $n$ ways, then the total number of ways both events can occur together is $m \times n$.
A firm is about to take on a new sales manager and a new receptionist. There are 6 applicants for the sales manager's job and 10 for that of the receptionist. How many ways can the pair be chosen?
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting (Multiplication Rule): If a series of sequential choices need to be made, where the first choice can be made in $m_1$ ways, the second in $m_2$ ways, the third in $m_3$ ways, and so on, then the total number of ways to complete the sequence is $m_1 \times m_2 \times m_3 \times ... \times m_n$.
The Khanna family (Dad, Mum, Sia, and Jeet) move to a new district, and they decide that each person will register with a different dentist. There are 6 dentists in the district, how many ways can this family register?
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting (Multiplication Rule): The number of ways to arrange $n$ distinct objects sequentially in $n$ positions is $n \times (n-1) \times (n-2) \times ... \times 1 = n!$.
Five children are running a race. How many different ways could they finish the race?
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting (Multiplication Rule): If an event involves multiple independent choices, the total number of outcomes is the product of the number of choices available at each step.
How many integers are there less than 1000, ending with 3, 6 or 9?
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting (Multiplication Rule): If a task consists of $k$ consecutive independent stages, with $n_1, n_2, ..., n_k$ choices at each stage, the total number of ways to perform the task is $n_1 \times n_2 \times ... \times n_k$.
A restaurant offers a choice of 3 salads, 5 main dishes, and 2 desserts. Use the fundamental principle of counting to find the number of different 3-course meals that can be selected.
Comprehensive Algebra
MCQ
Concept: Permutation of $n$ distinct items: The number of ways to arrange $n$ distinct objects in a line is given by $n! = n \times (n-1) \times ... \times 1$.
A teacher has 5 different books that he wishes to arrange in a row. How many different arrangements are possible?
Comprehensive Algebra
MCQ
Concept: Permutation of $r$ objects from $n$ distinct objects: The number of ordered arrangements of $r$ objects chosen from $n$ distinct objects is given by $P(n, r) = \frac{n!}{(n-r)!}$.
Suppose the teacher in Example 8 wishes to place only 3 of the 5 books in a row. How many arrangements of 3 books are possible?
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting (Sum Rule and Multiplication Rule): If a task can be performed in mutually exclusive cases, the total number of ways is the sum of the number of ways for each case.
Suppose a hospital uses a light signal system with 4 distinct colours. A signal can be formed by lighting up 1, 2, 3, or 4 lights in a specific sequence. How many different signals can be produced?
Comprehensive Algebra
MCQ
Concept: Permutations and the Multiplication Principle of Counting. The total number of ways to arrange $r$ distinct items into $n$ distinct places is given by $P(n, r) = \frac{n!}{(n-r)!}$.
Four persons enter a railway carriage in which there are six seats. In how many ways can they take their places?
Comprehensive Algebra
MCQ
Concept: Permutation of $n$ distinct objects taken all at a time, which is given by $n! = n \times (n - 1) \times (n - 2) \times \dots \times 1$.
Four speakers expressed their desire to take the floor at a meeting. In how many ways is it possible to arrange them in the list of speakers?
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting (Multiplication Rule). If an event can occur in $m$ ways, followed by a second event in $n$ ways, and a third event in $p$ ways, then the total number of ways all three events can occur together is $m \times n \times p$.
There are four possible routes from police HQ to the bus station, four from the bus station to the bank, and four more from the bank to police HQ. How many ways can a police car patrol a circuit from police HQ to bus station to bank and back to HQ?
Comprehensive Algebra
MCQ
Concept: Permutation and the Multiplication Principle of Counting. When distinct items are placed without repetition, we use permutations $P(n, r) = \frac{n!}{(n-r)!}$. When repetition is allowed, each item has $n$ independent options, leading to $n^r$ total ways.
Four prisoners are being moved by train from one jail to another. If the train has eight coaches and each prisoner must travel in a different coach, in how many possible ways can the men travel on the train? How many ways would there be if they did not have to travel in different coaches?
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting (Multiplication Rule). If a task consists of several independent steps, the total number of ways to complete the task is the product of the number of ways to perform each individual step.
Certain registration numbers are formed from three different letters, chosen from the first ten letters of the alphabet, followed by a three digit number which must not begin with zero. Calculate how many registration numbers can be formed?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting. When filling consecutive places, the choice for each place depends on excluding the digit used in the immediately preceding place while allowing digits used in earlier positions to be reused.
How many numbers of $n$ digits can be made with the non-zero digits in which no two consecutive digits are the same?
Comprehensive Algebra
MCQ
Concept: Addition Principle of Counting (Sum Rule). If an event can occur in $m$ different ways, and another mutually exclusive event can occur in $n$ different ways, then the total number of ways in which either event can happen is $m + n$.
There are 30 persons in a group of which 20 are boys and 10 are girls. In how many ways can a group leader be selected if the group leader can either be a boy or a girl?
Comprehensive Algebra
MCQ
Concept: Addition Principle of Counting and Permutations. The total number of valid integers is found by summing the counts of 1-digit, 2-digit, and 3-digit integers with non-repeating digits.
How many of the first 1000 positive integers have distinct digits?
Comprehensive Algebra
MCQ
Concept: Addition Principle of Counting and Permutations/Multiplication Rule. The problem is solved by dividing into cases based on the number of digits (2-digit, 3-digit, and 4-digit numbers) and summing the results.
How many numbers between 10 and 10,000 can be formed by using the digits 1, 2, 3, 4, 5 if
(i) no digit is repeated in any number?
(ii) digits can be repeated?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting. The total number of distinct outfits formed by combining one item from each independent category is given by the product of the number of choices in each category.
A boy has five pairs of trousers and six shirts. His girlfriend has four skirts and seven tops. Who has the most choice of what to wear?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting without repetition. Selecting the first action leaves one fewer choice for the second action.
A room has six doors. In how many ways is it possible to enter by one door and leave by another?
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting (Multiplication Rule) for multiple independent selections.
How many different types of homes are available if a builder offers a choice of 5 basic plans, 3 roof styles, and 2 exterior finishes?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting across multiple independent attributes.
A tyre store carries 8 different sizes of tyres, each in both tube and tubeless variety, each with either nylon or rayon cord, and each with white sidewalls or plain black. How many different kinds of tyres does the store have?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting for combined product variations.
A mail order company offers 23 styles of ladies' slippers. If each style were available in 12 lengths, 3 widths and 6 colours, how many different kinds of ladies slippers would the warehouse have to keep in stock?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting with positional constraints (thousands place cannot be 0, and units place determines evenness).
From the digits 0, 1, 2, 3, 4, 5, 6 how many four digit numbers can be constructed? How many of these are even numbers?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle applied to fixed-length digit positions with restricted digit sets.
How many of the integers (whole numbers) between 10,000 and 100,000 have no digits other than 6, 7, or 8? How many have no digits other than 6, 7, 8 or 0?
Comprehensive Algebra
MCQ
Concept: Counting ordered integer pairs under bounds and non-negativity restrictions.
How many solutions in positive integers x and y are there of the equation x + y = 100? By a solution, we mean an ordered pair (x, y) that satisfies the equation. How many solutions are there in non-negative integers?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting. The total number of terms in an expanded product of sums with distinct variables is equal to the product of the number of terms in each factor.
Find the number of terms in the product (a + b + c)(d + e + f)(p + q + r + s)(x + y + u + v + w).
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting and Case Separation based on conditional choices.
A menu lists a choice of soup or orange juice for an appetizer, a choice of egg, chicken or fish for the dinner, and a choice of ice-cream or cake for dessert. A complete dinner consists of one choice in each case. Calculate: (i) How many different complete dinners are possible? (ii) How many complete dinners are there which have chicken for the dinner? (iii) How many complete dinners are available for a man who will eat cake only if he had egg?
Comprehensive Algebra
MCQ
Concept: Permutations of $n$ distinct objects taken $r$ at a time, given by the formula $P(n, r) = \frac{n!}{(n - r)!}$.
Suppose 8 people enter an event in a swim meet. In how many ways could the gold, silver, and bronze prizes be awarded?
Comprehensive Algebra
MCQ
Concept: Permutations of $n$ distinct objects taken $r$ at a time, given by the formula $P(n, r) = \frac{n!}{(n - r)!}$.
A group of students studies seven disciplines. In what ways is it possible to arrange the timetable for Monday if on this day of the week four lessons in different subjects are to take place?
Comprehensive Algebra
MCQ
Concept: Permutations of distinct objects. The number of ways to select and arrange $r$ distinct items from a set of $n$ distinct items is given by $P(n, r) = \frac{n!}{(n - r)!}$.
How many integers between 100 and 999 inclusive consist of distinct odd digits?
Comprehensive Algebra
MCQ
Concept: Divisibility rules and Permutations. A number is a multiple of 5 if its last digit (units place) is 0 or 5. Arranging $n$ distinct objects taken $r$ at a time without repetition is given by $P(n, r) = \frac{n!}{(n - r)!}$.
How many six digit numbers multiple of 5 can be formed from the digits 1, 2, 3, 4, 5, 6, provided the numbers thus formed have no repeated digits?
Comprehensive Algebra
MCQ
Concept: Permutations without repetition and the Multiplication Principle of Counting. The total arrangements of $r$ distinct items from $n$ available items is given by $P(n, r) = \frac{n!}{(n-r)!}$. For conditional counting (such as even numbers), constraints are applied to specific digit positions first.
How many numbers of three digits can be formed using the digits 1, 2, 3, 4, 5, without repetition of digits? How many of these are even?
Comprehensive Algebra
MCQ
Concept: Permutations without repetition and the exclusion of numbers with a leading zero. A number between 100 and 1000 is a 3-digit number, where the hundreds place cannot be 0. The total number of valid permutations is $P(n, r) - P(n-1, r-1)$ where $0$ is fixed in the first position.
How many numbers lying between 100 and 1000 can be formed with the digits 0, 1, 2, 3, 4, 5, if repetition of the digits is not allowed?
Comprehensive Algebra
MCQ
Concept: Permutation formula $P(n, r) = \frac{n!}{(n - r)!}$ and algebraic simplification of factorials.
If $^{k+5}P_{k+1} = \frac{11(k - 1)}{2} \times {^{k+3}P_k}$, then find the value of $k$.
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting with conditional constraints. When forming a number with specific properties (such as being odd), fill the constrained position (units digit) first, followed by the remaining positions without repetition.
How many 4-digit numbers can be formed from 3, 4, 5, 6, 7 without repetition, if the numbers must all be odd?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting with conditional constraints. When seating individuals with specific restrictions (such as driving ability), fill the constrained position (driver's seat) first, followed by the remaining positions.
Five friends are setting out on a journey in a 5-seater car. In how many ways can they seat themselves for the journey if only two of them can drive?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting with positional restrictions and alternating patterns.
A pop-group's spot on a variety show is to consist of three vocal numbers and two instrumentals. In how many ways can the 'spot' be arranged so that it begins and ends with a vocal and neither instrumental follows directly after the other?
Comprehensive Algebra
MCQ
Concept: Addition Principle and Permutations without repetition ($P(n, r) = \frac{n!}{(n - r)!}$). The total count is found by considering valid numbers broken down by digit length (3-digit and 4-digit numbers).
Find the number of numbers between 300 and 3000 that can be formed with the digits 0, 1, 2, 3, 4 and 5, no digit being repeated in any number.
Comprehensive Algebra
MCQ
Concept: Permutations without repetition with constraints on specific positions. When counting even numbers where 0 is among the available digits, the calculation is split into cases based on whether 0 occupies the units place or another even digit occupies the units place (since 0 cannot occupy the thousands place).
How many even numbers of four digits can be formed with the digits 0, 1, 2, 3, 4, 5 and 6 without repetition?
Comprehensive Algebra
MCQ
Concept: Addition Principle and Permutations without repetition ($P(n, r) = \frac{n!}{(n - r)!}$). The problem is solved by splitting into cases based on the digit placed at the thousands place.
How many numbers of four digits greater than 2300 can be formed with the digits 0, 1, 2, 3, 4, 5 and 6; no digit being repeated in any number?
Comprehensive Algebra
MCQ
Concept: Addition Principle of Counting and Permutations without repetition ($P(n, r) = \frac{n!}{(n - r)!}$). The total count is found by considering valid numbers of different digit lengths (1-digit to 5-digit numbers) where the leading digit cannot be 0.
How many positive numbers can be formed by using any number of the digits 0, 1, 2, 3 and 4; no digit being repeated in any number?
Comprehensive Algebra
MCQ
Concept: Permutations without repetition ($P(n, r) = \frac{n!}{(n - r)!}$) and positional constraints. A number between 400 and 1000 must be a 3-digit number whose hundreds digit satisfies the given inequality.
How many numbers between 400 and 1000 can be made with the digits 2, 3, 4, 5, 6 and 0, repetition not allowed?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting with non-zero restrictions on the leading digit. For a 3-digit number, the hundreds digit cannot be 0, while subsequent digits can include 0 as long as no digits repeat.
How many integers between 100 and 999 have distinct digits?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting with conditional constraints. When counting numbers with specific constraints (such as being odd and having distinct digits), fill the constrained units place first, followed by the hundreds place (which cannot be 0), and then the tens place.
Of the 648 integers between 100 and 999 with distinct digits, how many are odd numbers?
Comprehensive Algebra
MCQ
Concept: Properties and expansion of factorials, where $n! = n \times (n-1) \times (n-2) \times \dots \times 1$. Factorial expressions can be simplified by factoring out common terms or expanding the larger factorial in terms of smaller factorials.
Simplify the following expressions:
(i) $\frac{7! - 5!}{4!4!}$
(ii) $\frac{(n + 1)!}{(n - 1)!}$
(iii) $\frac{(2n)!}{n!}$
Comprehensive Algebra
MCQ
Concept: Permutations of $n$ distinct objects taken all at a time is given by $n!$.
In an experiment on social interaction, 6 people will sit in 6 seats in a row. In how many ways can this be done?
Comprehensive Algebra
MCQ
Concept: Permutations of $n$ distinct items taken $r$ at a time without repetition, $P(n, r) = \frac{n!}{(n - r)!}$.
In how many ways can 3 men each be given a hotel room of his own if there are 8 free rooms available?
Comprehensive Algebra
MCQ
Concept: Arranging $r$ distinct items out of $n$ available distinct items over $r$ days without repetition, $P(n, r) = \frac{n!}{(n - r)!}$.
A man can cook 9 different dinners. How many different sequences of dinner could he cook for a week if he didn't prepare the same dinner twice?
Comprehensive Algebra
MCQ
Concept: Permutations of selecting and ordering $r$ distinct courses out of $n$ available courses, $P(n, r) = \frac{n!}{(n - r)!}$.
A business school offers courses in typing, shorthand, transcription, business english, technical writing, and accounting. In how many ways can a student arrange a schedule if 3 courses are taken?
Comprehensive Algebra
MCQ
Concept: Permutations of $n$ objects in $n$ fixed positions, $n!$.
In how many different ways can four passengers be seated in a railway coach compartment for four?
Comprehensive Algebra
MCQ
Concept: Permutations of selecting $r$ positions from $n$ distinct individuals where order matters, $P(n, r) = \frac{n!}{(n - r)!}$.
A trade union committee consists of 9 persons and has to elect a chairman, a vice-chairman and a treasurer. How many various combinations can there be?
Comprehensive Algebra
MCQ
Concept: Solving algebraic equations involving permutation formulas $P(n, r) = \frac{n!}{(n - r)!}$.
How many elements should be taken so that the number of their permutations taken 4 at a time is 6 times greater than those taken 2 elements at a time?
Comprehensive Algebra
MCQ
Concept: Permutations with fixed positional restrictions.
Determine the number of permutations of the letters in the word ROCKET. How many permutations can be made so that the letter R is the first letter and ET are the last two letters?
Comprehensive Algebra
MCQ
Concept: Permutations of choosing $r$ ordered roles from $n$ distinct members, $P(n, r) = \frac{n!}{(n - r)!}$.
In a club with 15 members, how many ways can a slate of 3 officers consisting of president, vice-president, and secretary/treasurer be chosen?
Comprehensive Algebra
MCQ
Concept: Permutations of assigning players to distinct positions without repetition.
In how many ways can 5 players be assigned to the 5 positions on a basketball team, assuming that any player can play any position? In how many ways can 10 players be assigned to the 5 positions?
Comprehensive Algebra
MCQ
Concept: Permutations of assigning $n$ distinct items into $k$ distinct slots ($k > n$) without repetition, represented by $P(k, n) = \frac{k!}{(k - n)!}$.
In how many ways can all of $n$ distinct objects be put in $k$ distinct boxes, not more than one in each box, if there are more boxes than things ($k > n$)?
Comprehensive Algebra
MCQ
Concept: Permutation with repetition. Each distinct object (marble) can independently be placed into any of the available options (pockets). If there are $n$ options available for each of the $r$ objects, the total number of ways is $n^r$.
A child has four pockets and three marbles. In how many ways can the child put the marbles in its pockets?
Comprehensive Algebra
MCQ
Concept: Permutation with repetition where each of the $r$ places can independently take any of the $n$ available choices ($n^r$).
A number lock has four rings, each with ten different digits (0 to 9). How many different attempts to open the lock might one need to make in order to find the correct permutation?
Comprehensive Algebra
MCQ
Concept: Permutation with repetition for binary choices. For a sequence of length $r$ with $n$ possible symbols at each position, total arrangements = $n^r$.
The letters of the Morse code are sequences of dots and dashes. How many different letters can be formed by using 5 symbols?
Comprehensive Algebra
MCQ
Concept: Comparing permutations with repetition ($n^r$) and permutations without repetition ($P(n, r)$).
How many 3-letter code words (permutations) can be made from the word ANCHOR if:
(i) we can repeat letters?
(ii) we cannot repeat letters?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting with restrictions on initial positions and repetition allowed.
How many car registration plates can be made, using two letters followed by four digits (e.g., RJ 6610)? (Zero is not allowed as the first of the four digits).
Comprehensive Algebra
MCQ
Concept: Permutation with repetition and counting non-empty subsets ($2^k - 1$).
A student appears in an objective test which contains 10 multiple choice questions. Each question has four choices and one correct answer.
(i) What is the maximum number of different answers can the student give?
(ii) How will the answer change if each question may have more than one correct answers?
Comprehensive Algebra
MCQ
Concept: Permutation with repetition. Each toss of a coin has 2 possible outcomes (Heads or Tails). For $n$ independent tosses, the number of outcomes is $2^n$.
How many different outcomes are there in an experiment consisting of $n$ tosses of a coin?
Comprehensive Algebra
MCQ
Concept: Total number of possible combinations minus the single successful combination that opens the lock.
A letter lock consists of three rings each marked with fifteen different letters. Find in how many ways it is possible to make an unsuccessful attempt to open the lock?
Comprehensive Algebra
MCQ
Concept: Permutation with repetition where each of the $r$ stalls can independently take any of the $n$ available types of animals ($n^r$).
There are stalls for 12 animals in a ship. In how many ways the shipload can be made if there are cows, calves and horses to be transported, animals of each kind being not less than 12?
Comprehensive Algebra
MCQ
Concept: Permutation with repetition where each object (delegate) can independently choose any option (hotel), giving $n^r$ total ways.
In how many ways 5 delegates can be put in 6 hotels of a city if there is no restriction?
Comprehensive Algebra
MCQ
Concept: Permutations with repetition and conditional choice reduction for consecutive items.
In how many ways can a ten question multiple choice examination be answered if there are four choices a, b, c and d to each question? If no two consecutive questions are answered the same way, how many ways are there?
Comprehensive Algebra
MCQ
Concept: Calculating the total number of permutations with repetition ($10^5$) and converting time units to compare against available working hours.
A safe is locked by a device consisting of five disks with the digits 0, 1, 2, ..., 9 on each of them. The safe gets unlocked by dialing a certain combination of digits. Will ten days be enough to open the safe if the working day lasts 13 hours and it takes five seconds to dial one combination of digits?
Comprehensive Algebra
MCQ
Concept: Sum of permutations with repetition for 1-digit through 7-digit numbers using 10 possible digits (0-9).
How many different telephone numbers are there if it is assumed that each number contains not more than seven digits (a telephone number may begin with a zero)?
Comprehensive Algebra
MCQ
Concept: Comparing unrestricted arrangement ($n^r$), arrangement without repetition ($P(n, r)$), and complementary counting ($n^r - n$).
In how many ways can 5 delegates be put in 6 hotels of a city if:
(i) there is no restriction?
(ii) no two delegates can stay together?
(iii) all the delegates do not stay in the same hotel?
Comprehensive Algebra
MCQ
Concept: Counting options per issue with repetition allowed, minus the fully restricted case (abstaining on all issues).
The members of a club are to vote "yes" or "no" on each of eight issues. In marking his ballot, a member has the option of abstaining on as many as seven of the issues, but he should not abstain in all eight cases. In how many ways can a ballot be marked?
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting. Selecting winning students from $20$ available candidates for distinct prizes across different subjects.
In a school there are two prizes for excellence in Mathematics (1st and 2nd), two in Chemistry (1st and 2nd), and only one in Physics (1st). In how many ways can these prizes be awarded to 20 students?
Comprehensive Algebra
MCQ
Concept: Permutations with specific positional constraints, both with and without repetition.
How many different 4-letter radio station call letters can be made:
(a) if the first letter must be K or W and no letter may be repeated?
(b) if repeats are allowed (but the first letter is K or W)?
(c) How many of the 4-letter call letters (starting with K or W) with no repeats end in R?
Comprehensive Algebra
MCQ
Concept: Multiplication principle combining letters ($26$) and digits ($10$), with and without repetition.
For many years, Delhi used 3 letters followed by 3 digits on its automobile license plates.
(a) How many different license plates are possible with this arrangement?
(b) How many plates are possible if no letter or digit can be repeated on a single plate?
Comprehensive Algebra
MCQ
Concept: Permutations with repetition ($n^r$). Each ring can independently be worn on any of the available fingers, so for $r$ rings and $n$ fingers, the total number of ways is $n^r$.
In how many ways can 6 rings be worn on the four fingers of one hand?
Comprehensive Algebra
MCQ
Concept: Combining unrestricted placement ($n^r$), placement without repetition ($P(n, r)$), and complementary counting ($n^r - \text{restricted cases}$).
In how many ways four friends can put up in 8 hotels of a town if
(i) There is no restriction?
(ii) No two friends can stay together?
(iii) All the friends do not stay in same hotel?
Comprehensive Algebra
MCQ
Concept: Sum of digits in a specific place value across all permutations. If $n$ distinct non-zero digits are taken all at a time without repetition, each digit appears in the unit place $(n - 1)!$ times. The sum of digits at the unit place is given by $(n - 1)! \sum d_i$.
Find the sum of the digits in the unit place of all numbers formed with the help of 3, 4, 5, 6 taken all at a time.
Comprehensive Algebra
MCQ
Concept: Sum of numbers formed using $n$ distinct digits including 0. The total sum is found by calculating the contribution of non-zero digits across all place values, accounting for the condition that 0 cannot occupy the thousands place.
Find the sum of all the four-digit numbers that can be formed with the digits 0, 1, 2 and 3 (repetition of digits not allowed).
Comprehensive Algebra
MCQ
Concept: Sum of numbers formed using digits with repetitions. Calculating the frequency of each distinct digit at each place value using permutations of multiset items.
Find the sum of all the 4-digit numbers that can be formed with the digits 1, 2, 2 and 3.
Comprehensive Algebra
MCQ
Concept: Sum of all $n$-digit numbers formed using $n$ distinct non-zero digits without repetition:
$\text{Sum} = (n - 1)! \times (\sum d_i) \times \left(\frac{10^n - 1}{9}\right)$.
Find the sum of all five-digit numbers that can be formed using the digits 1, 2, 3, 4 and 5 (repetition of digits not allowed).
Comprehensive Algebra
MCQ
Concept: Recurrence relation for permutations. Counting $r$-permutations of $n$ distinct items by partitioning into two disjoint cases: permutations that contain a specified item versus permutations that do not contain that specified item.
Prove that $P(n, r) = r \times P(n - 1, r - 1) + P(n - 1, r)$. Which of the following correctly describes this algebraic identity?
Comprehensive Algebra
MCQ
Concept: Sum of permutations $P(n, k)$ for varying lengths $k = 1, 2, \dots, n$.
Find the total number of signals that can be made by five flags of different colours when any number of them may be used.
Comprehensive Algebra
MCQ
Concept: Counting arrangements with restrictions using complementary counting and inclusion-exclusion principle for distinct colour requirements.
There are counters available in 3 different colours (at least four of each colour). Counters are all alike except for the colour. If $m$ denotes the number of arrangements of four counters if no arrangement consists of counters of same colour and $n$ denotes the corresponding figure when every arrangement consists of counters of each colour, then find the value of $m / n$.
Comprehensive Algebra
MCQ
Concept: Permutations and Lexicographical Ranking
If all the letters of the word QUEST are arranged in all possible ways and put in dictionary order, then find the rank of the given word.
Comprehensive Algebra
MCQ
Concept: Permutations and Lexicographical Ranking
The letters of the word OUGHT are written in all possible orders and these words rewritten out as in a dictionary. Find the rank of the word TOUGH in this dictionary.
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting and Parity Analysis
Find the number of 7-digit numbers the sum of whose digits is even.
Comprehensive Algebra
MCQ
Concept: Multiplication Principle of Counting with Restrictions
A new club flag is to be designed with 6 vertical stripes using some or all of the colours yellow, green, blue and red. In how many ways can this be done so that no two adjacent stripes have the same colour?
Comprehensive Algebra
MCQ
Concept: Permutations with Repetition
How many different five-digit numbers are there (leading zeros not allowed)?
Comprehensive Algebra
MCQ
Concept: Counting Principles for Even Numbers
How many even 5-digit numbers are there?
Comprehensive Algebra
MCQ
Concept: Palindromic Numbers and Counting Principle
How many 5-digit numbers are there that are the same when the order of their digits is reversed (e.g., 14341)?
Comprehensive Algebra
MCQ
Concept: Permutations and Counting Principles
Find the number of positive integers with distinct digits.
Comprehensive Algebra
MCQ
Concept: Divisibility Rule of 9 and Permutations
Find the number of 9 digit numbers divisible by 9 which can be formed using the digits from 0 to 9 without repetition of digits.
Comprehensive Algebra
MCQ
Concept: Sum of Numbers Formed by Permutation of Digits
Find the sum of all the four digit numbers that can be formed with the digits 3, 2, 3, 4.
Comprehensive Algebra
MCQ
Concept: Sum of Digits at Place Values
Find the sum of all numbers greater than 10,000 formed with the digits 0, 2, 4, 6 and 8; no digit being repeated in any number.
Comprehensive Algebra
MCQ
Concept: Sum of Permutations of Digits with Zero Present
Find the sum of all the 4 digit numbers that can be formed with the digits 0, 2, 3 and 5.
Comprehensive Algebra
MCQ
Concept: Lexicographical Order and Rank of a Word
The letters of the word RANDOM are written in all possible orders and these words are written out as in a dictionary. Find the rank of the word RANDOM.
Comprehensive Algebra
MCQ
Concept: Linear Permutation and Relative Position Constraints
In how many ways can six persons A, B, C, D, E, F line up at a railway booking window? In how many of these A stands first? In how many of these A gets the ticket before B?
Comprehensive Algebra
MCQ
Concept: Restricted Permutations and Combinations with/without Repetition
How many numbers greater than 1000, but not greater than 4000 can be formed with the digits 0, 1, 2, 3, 4, if: (i) repetition of digits is allowed? (ii) repetition of digits is not allowed?
Comprehensive Algebra
MCQ
Concept: Divisibility Rule of 3 and Combinatorial Selection
How many five digits numbers divisible by 3 can be formed using the digits 0, 1, 2, 3, 4, 7 and 8 if each digit is to be used at most once.
Comprehensive Algebra
MCQ
Concept: Fundamental Multiplication Principle of Counting
In how many ways can 6 boys and 5 girls be arranged for a group photograph if the girls are to sit on chairs in a row and the boys are to stand in a row behind them?
Comprehensive Algebra
MCQ
Concept: Forming Numbers with Specific Magnitude Constraints
How many different numbers greater than 5000 can be formed with the digits 0, 1, 5, 9, no digit being repeated?
Comprehensive Algebra
MCQ
Concept: Counting Numbers in Given Range
Find the number of numbers lying between 300 and 4000 that can be formed with the digits 0, 1, 2, 3, 4, 5; no digit being repeated.
Comprehensive Algebra
MCQ
Concept: Parity of Digit Sums and Fundamental Counting Rule
How many five digits numbers are there whose sum of digits is odd?
Comprehensive Algebra
MCQ
Concept: Divisibility Rules and Position Constraints
If repetition of digits is not allowed how many numbers of four digits divisible by 5 can be formed with the digits 0, 4, 5, 6, 7?
Comprehensive Algebra
MCQ
Concept: Divisibility by 25 without Repetition
Find the number of numbers divisible by 25 that can be formed using only the digits 1, 2, 3, 4, 5 and 0 taken five at a time.
Comprehensive Algebra
MCQ
Concept: Combinations vs Permutations (Selection vs Ordering)
A sales representative has 10 accounts in a certain city.
(a) In how many ways can 3 accounts be selected to call on?
(b) In how many ways can calls be scheduled for 3 of the 10 accounts?
Comprehensive Algebra
MCQ
Concept: Combination of 2 Elements from $n$ Distinct Elements
How many matches will be played in a football championship of 16 participants if every two teams play with each other once?
Comprehensive Algebra
MCQ
Concept: Selection of $r$ Objects from $n$ Objects
Two ambulance attendants are needed in any emergency and there are six men on duty. In how many ways can the two be chosen?
Comprehensive Algebra
MCQ
Concept: Division into Groups / Selecting Subsets
In how many ways can 7 different books be given to two students if one student is to have 4 books and the other is to have 3 books?
Comprehensive Algebra
MCQ
Concept: Combinatorial Selection and Inclusion Constraints
A teacher takes 3 children from her class to the zoo at a time as often as she can, but she does not take the same three children to the zoo more than once. She finds that she goes to the zoo 84 times more than a particular child goes to the zoo. Find the number of children in her class.
Comprehensive Algebra
MCQ
Concept: Properties of Combinations and Factorials
Prove that the product of $r$ consecutive integers is divisible by $r!$.
Comprehensive Algebra
MCQ
Concept: Algebraic Equations Involving Permutations and Combinations
Solve the equation $^{x+3}P_2 = ^{x+2}C_3 + 20$.
Comprehensive Algebra
MCQ
Concept: Division of Distinct Objects into Specified Group Sizes
Suppose we have 10 social workers and we wish them to work in groups of 2, 3 and 5. How many ways can we split them up into groups of the right size?
Comprehensive Algebra
MCQ
Concept: Partitioning a Set into Distinct Named Groups
In this year's school play the cast consists of 5 members of a royal family, 15 soldiers, and 30 peasants. How many ways can the cast of 50 pupils be divided among these three groups?
Comprehensive Algebra
MCQ
Concept: Combinations with Repetition and Identical Objects on Restricted Positions
How many ways can 12 identical white pawns and 12 identical black pawns be placed on the black squares of an $8 \times 8$ chessboard?
Comprehensive Algebra
MCQ
Concept: Counting Pairs in Rows and Columns
How many ways are there to place 2 identical rooks in a common row or column of an $8 \times 8$ chessboard?
Comprehensive Algebra
MCQ
Concept: Complementary Counting on Restricted Grids
How many ways are there to place 2 identical kings on an $8 \times 8$ chessboard so that the kings are not in adjacent squares in the same row or column?
Comprehensive Algebra
MCQ
Concept: Combinations and Modular Arithmetic / Complementary Counting
All possible two-factor products are formed from the numbers 1, 2, 3, ..., 100. How many numbers out of the total obtained are multiples of 3?
Comprehensive Algebra
MCQ
Concept: Fundamental Principle of Counting and Combinations
A basketball coach must select two attackers and two defenders from among three attackers and five defenders. How many different combinations of attackers and defenders can he select?
Comprehensive Algebra
MCQ
Concept: Addition and Multiplication Principles in Combinatorial Selection
A cricket team of 11 men is to be chosen from 15 men. Four of the 15 can bowl and two others can keep wicket. If the team is must include only one wicket keeper and at least three bowlers, in how many ways can it be chosen?
Comprehensive Algebra
MCQ
Concept: Case Analysis and Combination Sum Rule
A group of students consists of 4 boys and 5 girls. Find the number of ways of selecting a team of at least 3 boys and 4 girls.
Comprehensive Algebra
MCQ
Concept: Pascal's Identity for Combinations
Evaluate $^nC_r + \sum_{j=0}^{3} {^{n+j}C_{r+1+j}}$.
Comprehensive Algebra
MCQ
Concept: Maximum Value of Combination $^{n}C_r$ for Odd $n$
A class has 21 students. The class teacher has been asked to make groups of $r$ students each and go to the zoo taking one group at a time. Find the size of the group for which the teacher goes the maximum number of times to the zoo.
Comprehensive Algebra
MCQ
Concept: Ratio Properties of Combinations and Factorial Simplification
If $^{n+1}C_{r+1} : ^nC_r : ^{n-1}C_{r-1} = 11 : 6 : 3$, then find the value of $nr$.
Comprehensive Algebra
MCQ
Concept: Consecutive Combination Ratios and System of Linear Equations
If $^{n}C_{r-1} = 36$, $^nC_r = 84$, and $^{n}C_{r+1} = 126$, then find $r$.
Comprehensive Algebra
MCQ
Concept: Vandermonde's Identity and Combinatorial Proof
Prove or identify the correct algebraic form of Vandermonde's Identity: $^{n+m}C_r = \sum_{k=0}^{r} {^nC_k \cdot ^mC_{r-k}}$.
Comprehensive Algebra
MCQ
Concept: Combinations and Elementary Probability Principles with Playing Cards
What is the number of ways of choosing 4 cards from a pack of 52 playing cards? In how many of these:
(i) four cards are of the same suit,
(ii) four cards belong to four different suits,
(iii) are face cards,
(iv) two are red cards and two are black cards,
(v) cards are of the same color?
Comprehensive Algebra
MCQ
Concept: Permutation (Order Matters) vs Combination (Order Does Not Matter)
Which of the following everyday activities involve permutations, and which involve combinations only?
(i) Choosing a cricket team from a class of 24 boys.
(ii) Deciding which of the boys will bat first, second, and so on.
(iii) Deciding which three books to borrow from a library.
(iv) Planning the best sequence in which to decorate the rooms in my house.
(v) Planting a row of rose-bushes so that red and yellow flowers alternate.
Comprehensive Algebra
MCQ
Concept: Geometric Combinations from Vertices
How many triangles can be constructed by connecting the vertices of an octagon?
Comprehensive Algebra
MCQ
Concept: Selection of Objects (Combinations)
How many ways can a traffic warden with 3 parking tickets left in his book, give them to three out of the seven cars he find that have over-parked?
Comprehensive Algebra
MCQ
Concept: Forming Subsets of Equal Size
A party of eight people arrive at a river and a boatman agrees to take them across in two groups of four. In how many ways can the first boatload be chosen?
Comprehensive Algebra
MCQ
Concept: Combinatoric Selection and Time Intervals
In a local police station, a different combination of three constables is selected daily for duty. If there are ten constables available and the system operates every day except Sunday, how many weeks will go by before the same three constables are on duty again together?
Comprehensive Algebra
MCQ
Concept: Combinations and Modular Arithmetic / Complementary Counting
All possible two factor products are formed from the numbers 1, 2, 3, ..., 100. How many numbers out of the total obtained are multiples of 3?
Comprehensive Algebra
MCQ
Concept: Domain Constraints of Combinations $^nC_r$
Find the domain of definition of the function $f(x) = ^{2x-8}C_{x+1}$ and the set of its values.
Comprehensive Algebra
MCQ
Concept: Ratio of Consecutive Combinations
Solve the given inequalities:
(a) $^{10}C_{x-1} > 2 \cdot ^{10}C_x$
(b) $8 \cdot ^{105}C_x < 3 \cdot ^{105}C_{x+1}$
Comprehensive Algebra
MCQ
Concept: Combinatorial Inequality Solving
Find the positive integral values of $x$ such that $^{x-1}C_4 - ^{x-1}C_3 - \frac{5}{4}(x-2)(x-3) < 0$.
Comprehensive Algebra
MCQ
Concept: Multinomial Partitioning into Unassigned Groups
Twelve people are waiting for a bus. When it comes it only has room for 6 on top and 4 downstairs. So in how many ways could you form the three groups (those who go upstairs, downstairs or wait)?
Comprehensive Algebra
MCQ
Concept: Combinatorial Equations in Game Tournaments
There are $m$ men and 2 women participating in a chess tournament. Every participant plays two games with every other participant. If the number of games played by the men between themselves exceeds by 66 the number of games played between men and women, then find the value of $m$ and the total number of games played in the tournament.
Comprehensive Algebra
MCQ
Concept: Selection of Objects from Distinct Subsets
A bag contains 5 black and 6 red balls, all balls being different. Determine the number of ways in which 2 black and 3 red balls can be selected.
Comprehensive Algebra
MCQ
Concept: Sequential Selection with Permutation and Combination
A meeting of 40 people must choose a chairman, a secretary and 5 members of a committee. How many different committees can be formed?
Comprehensive Algebra
MCQ
Concept: Independent Combinatorial Choices
A team consists of two house painters, three plasterers and one joiner. How many different teams can be formed from a staff of fifteen house painters, ten plasterers and five joiners?
Comprehensive Algebra
MCQ
Concept: Complementary Counting for "At Least One"
Ten cards have been taken from a pack of 52. In how many cases will there be at least one ace among the selected cards?
Comprehensive Algebra
MCQ
Concept: Selection with Dependent Suit Restrictions
How many ways are there of choosing a hand of 6 cards containing an ace and a king of the same suit from a pack of 52 cards?
Comprehensive Algebra
MCQ
Concept: Constrained Category Selection
In how many ways can a cricket team be selected from a group of 25 players containing 10 batsmen, 8 bowlers, 5 all-rounders and 2 wicket keepers? Assume that the team of 11 players requires 5 batsmen, 3 all-rounders, 2 bowlers and 1 wicket keeper.
Comprehensive Algebra
MCQ
Concept: Permutations of Objects Not All Distinct (Alike Objects)
In how many ways can the letters of the word DADDY be permuted among themselves?
Comprehensive Algebra
MCQ
Concept: Permutations of Objects Not All Distinct (Alike Objects)
In how many ways can you permute the letters of the word VIVEKANANDA?
Comprehensive Algebra
MCQ
Concept: Permutations of Multiset / Like Elements
A train time table must be compiled for various days of the week so that two trains a day depart for three days, one train a day for two days, and three trains a day for two days. How many different time tables can be compiled?
Comprehensive Algebra
MCQ
Concept: Permutations with Repetition and Divisibility Constraints
Find the number of six digit numbers not divisible by 5 that can be formed by using the digits of the number 121202.
Comprehensive Algebra
MCQ
Concept: Complementary Counting on Digits
In a certain country, the numerals in car registration marks range from 1 to 999. Find the number of cases in which the first local car which you see while visiting that country has at least two digits the same in its registration mark.
Comprehensive Algebra
MCQ
Concept: Combinatorial Position Selection and Digit Placement
Find the number of seven digit numbers which have exactly three 9's.
Comprehensive Algebra
MCQ
Concept: Complementary Counting for Grouped Permutations
In how many ways can 5 identical black balls, 7 identical red balls, and 6 identical green balls be arranged in a row so that at least one ball is separated from balls of the same color?
Comprehensive Algebra
MCQ
Concept: Lexicographical Rank of Words with Repeated Letters
A dictionary is printed consisting of 7-lettered words that can be made with the letters of the word CRICKET. If the words are printed in the alphabetic order, as in an ordinary dictionary, find the position of the word CRICKET in that dictionary.
Comprehensive Algebra
MCQ
Concept: Case Analysis and Permutations of Identical Objects in Game Series
Two players A and B play a series of games of chess. The winning player in any game gets 1 point while the losing player gets 0 point. The player who achieves 4 points first, wins the series. If no game ends in a draw, find the number of ways in which the series can be won by A.
Comprehensive Algebra
MCQ
Concept: Permutations of Objects Not All Distinct (Alike Objects)
In how many ways can you permute the letters of the word CONSTITUTION?
Comprehensive Algebra
MCQ
Concept: Permutations with Repeated and Distinct Letters
How many different permutations can be formed from the letters contained in the following words: (a) ZEBRA, (b) BAZAR, (c) SILICIC, (d) ABRACADABRA?
Comprehensive Algebra
MCQ
Concept: Arrangement of Identical Objects in a Line
In how many ways can we plant a line of 10 bulbs consisting of 5 roses, 3 daffodils, and 2 sunflowers?
Comprehensive Algebra
MCQ
Concept: Sum of Numbers Formed by Permutation of Digits with Repetition
Find the sum of all the numbers that can be formed using all the digits 2, 3, 3, 4, 4, 4.
Comprehensive Algebra
MCQ
Concept: Permutations with Specific Subset Selection and Repetitions
There are $4n$ things of which $n$ are alike and all the rest different. Find the number of permutations of $4n$ things taken $2n$ at a time, each permutation containing the $n$ like things.
Comprehensive Algebra
MCQ
Concept: Multinomial Permutation and Unassigned Outcomes
How many ways of tossing 12 dice are there in which each of the values 2, 3, 4, 5, 6 occurs twice?
Comprehensive Algebra
MCQ
Concept: Binomial Sequence Combinations
We toss a coin and assume a head is a success and a tail is a failure. How many trails will lead to 52 successes out of 100 tosses of the coin?
Comprehensive Algebra
MCQ
Concept: Permutations with Repeated Digits and Parity Restrictions
How many seven digits numbers can be formed with the digits 1, 2, 2, 2, 3, 3, 5? How many of them are odd?
Comprehensive Algebra
MCQ
Concept: Sum of Geometric Series in Permutations with Repetition
A biologist is studying patterns of male(M) and female(F) children in families. A family type is designated by a code; for example, FMM denotes a family of three children of which the oldest is a female and the other two males. Note that FMM, MFM, and MMF are different types. How many family types are there among families with at least one but not more than seven children?
Comprehensive Algebra
MCQ
Concept: Rank of a Word with Repeated Letters
The letters of the word SURITI are written in all possible orders and are written down as in a dictionary. Find the rank of the word SURITI.
Comprehensive Algebra
MCQ
Concept: Permutations under Restrictions and Complementary Counting
Consider the set $\{a, b, c, d, e\}$. How many three-letter words can be made out of them, with or without meaning? How many of these will have at least one vowel in them? Answer these questions for both cases when repetitions of letters are allowed and when repetitions of letters are not allowed.
Comprehensive Algebra
MCQ
Concept: Permutations with Position Restrictions
How many different words can be formed with the letters of the word PENCIL when vowels occupy even places?
Comprehensive Algebra
MCQ
Concept: Fixed Position Permutations
How many of the permutations of the word ENGLISH will:
(i) start with E?
(ii) end with H?
(iii) start with E and end with H?
Comprehensive Algebra
MCQ
Concept: Sum of Digits at Place Values with Middle Place Restrictions
Three-digit numbers in which the middle digit is a perfect square are formed using the digits 1 to 9. Find the sum of all such numbers.
Comprehensive Algebra
MCQ
Concept: String Method / Grouping Identical Elements Together
A library has two books each having three copies and three other books each having two copies. In how many ways can all these books be arranged in a shelf so that copies of the same book are not separated?
Comprehensive Algebra
MCQ
Concept: String Method with Internal Permutations
In how many ways can 8 Indians, 4 Americans, and 4 Englishmen be seated in a row so that all persons of the same nationality sit together?
Comprehensive Algebra
MCQ
Concept: String Method / Grouping Permutations with Repeated Letters
How many different words can be formed with the letters of the word 'UNIVERSITY' so that all the vowels are together?
Comprehensive Algebra
MCQ
Concept: Relative Order and Block Permutations
Five persons are to address a meeting. If a specified speaker is to speak before another specified speaker, find:
(i) the number of ways in which this could be arranged.
(ii) how many of these arrangements will have the first speaker come immediately before the second?
Comprehensive Algebra
MCQ
Concept: Gap and Subgroup Permutation Arrangements
10 IIT and 2 PET students sit in a row. Find the number of ways in which exactly 3 IIT students sit between 2 PET students.
Comprehensive Algebra
MCQ
Concept: Complementary Counting for Unseparated Elements
In a class of 10 students, there are 3 girls. In how many ways can they be arranged in a row such that all the three girls do not sit together?
Comprehensive Algebra
MCQ
Concept: Non-adjacent Permutations via Complementary Subtraction
Determine the number of permutations of $n$ elements taken all at a time in which two given elements $a$ and $b$ are not adjacent.
Comprehensive Algebra
MCQ
Concept: Gap Method for Non-Adjacent Permutations
There are 10 candidates for an examination out of which 4 are appearing in Mathematics and the remaining 6 are appearing in different subjects. In how many ways can they be seated in a row so that no two mathematics candidates are together?
Comprehensive Algebra
MCQ
Concept: Gap Method with Permutations of Subsets
Of the $30!$ permutations of the integers $1, 2, 3, \dots, 30$, how many have the property that multiples of 3 are not in adjacent places (that is, no two of the integers $3, 6, 9, \dots, 27, 30$ are adjacent)?
Comprehensive Algebra
MCQ
Concept: Gap Method and Inclusion-Exclusion Principles
In how many ways can the letters AAABBCD be arranged so that:
(i) the two B's are together but no two A's are together?
(ii) no two B's and no two A's are together?
Comprehensive Algebra
MCQ
Concept: Permutations with Repeated Objects and Restrictions
Find the total number of arrangements of the letters of the word INDEPENDENCE. How many of these:
(i) do the words start with P?
(ii) do all the vowels always occur together?
(iii) do all the vowels never occur together?
Comprehensive Algebra
MCQ
Concept: To find the number of arrangements where a specific group of items does not sit together, subtract the number of arrangements where they sit together as a single unit from the total number of unrestricted arrangements.
In how many ways can 5 boys and 3 girls be seated in a row so that all the three girls do not sit together?
Comprehensive Algebra
MCQ
Concept: When two equal groups of items need to be arranged alternately in a row, there are two distinct starting patterns: either the first group takes the odd positions or the second group takes the odd positions. The total number of arrangements is the sum of the arrangements from both cases.
In how many ways can 4 boys and 4 girls be seated in a row so that boys and girls sit alternate?
Comprehensive Algebra
MCQ
Concept: When the number of items in one group exceeds the other by 1, the group with more items must occupy the odd-numbered positions (1st, 3rd, 5th, etc.) so that no two items of the same group sit adjacent to each other.
In how many ways can 4 boys and 3 girls be seated in a row so that they sit alternately?
Comprehensive Algebra
MCQ
Concept: For alternating seating arrangements where one category has one more person than the other, there is only one valid seating pattern. The larger group takes all odd spots and the smaller group takes all even spots.
In how many ways can 4 boys and 3 girls be seated in a row so that boys and girls sit alternate?
Comprehensive Algebra
MCQ
Concept: When two groups have an equal number of members, alternating arrangements can begin with either group. The total number of ways is the sum of arrangements starting with the first group and arrangements starting with the second group.
In how many ways can 4 boys and 4 girls be seated in a row so that boys and girls sit alternate?
Comprehensive Algebra
MCQ
Concept: To form three-letter words with a vowel in the middle, consider each distinct vowel available in the word separately. For each middle vowel, count the number of valid arrangements for the remaining two outer positions, accounting for whether the outer letters are distinct or identical.
How many words of three letters can be formed from the word 'Keppelin', a vowel being always in the middle?
Comprehensive Algebra
MCQ
Concept: To form a number where specific digits occupy specific positions, find the number of permutations of the odd digits among the odd positions and multiply it by the number of permutations of the even digits among the even positions, accounting for repeated digits.
How many numbers can be formed with the digits 1, 2, 3, 4, 3, 2, 1 so that the odd digits always occupy the odd places?
Comprehensive Algebra
MCQ
Concept: First select the person for the steering position from the available steering specialists. Then place the restricted rowers on their designated side, select the remaining rowers required for both sides, and multiply by the permutations of the rowers on each side.
An eight-oared boat is to be manned by a crew chosen from 11 men of whom 3 can steer but cannot row and the rest cannot steer. In how many ways can the crew be arranged if two of the men can only row on the bow side?
Comprehensive Algebra
MCQ
Concept: When specific letters must stay together, treat them as a single combined block. To ensure other identical letters remain separated, place all other letters first and then arrange the restricted letters in the available spaces created between them.
How many seven-letter words can be formed by using the letters of the word SUCCESS so that:
(a) the two C are together but no two S are together?
(b) no two C and no two S are together?
Comprehensive Algebra
MCQ
Concept: When two specific items must be side by side, treat them as a single block to reduce the total number of items, then multiply by the internal arrangements of the block. To find the arrangements where they are not side by side, subtract the side-by-side arrangements from the total unrestricted arrangements.
In how many ways can 6 books be arranged on a shelf if (a) two particular books must be side by side and (b) if these two books must not be side by side?
Comprehensive Algebra
MCQ
Concept: To arrange identical or distinct copies grouped by topic together, treat each topic as a single group. First, arrange the groups, and then multiply by the internal permutations of the books within each group (accounting for identical copies using permutations of multisets).
I have 2 copies of a statistics book, 2 copies of an algebra book, 3 copies of a calculus book, and 1 copy of a book on astronomy. In how many ways can I arrange these books on a shelf so that books of each topic are together?
Comprehensive Algebra
MCQ
Concept: To keep two specified volumes together in a large set, group them as one unit. To keep two volumes apart, subtract the number of arrangements where they are together from the total factorial of the set size.
A collection of 30 volumes is on a book shelf. How many ways are there of arranging the series (a) for volumes 1 and 2 to be side by side? (b) for volumes 3 and 4 not to be side by side?
Comprehensive Algebra
MCQ
Concept: Calculate the total valid 4-digit numbers using the allowed digits (ensuring the thousand's place is non-zero), and subtract the number of 4-digit numbers formed without using the digit 1 at all.
How many different four-digit numbers can be formed from the digits 0, 1, 2, 3, 4, 5, 6, 7 so that each number contains one digit 1?
Comprehensive Algebra
MCQ
Concept: (i) Fix the first and last letters and arrange the remaining letters accounting for repeated letters.
(ii) Group all vowels as a single unit and arrange the remaining letters and internal vowels.
(iii) Use position analysis for fixed gaps between two specified letters.
In how many ways can the letters of the word PERMUTATIONS be arranged if (i) words start with P and end with S, (ii) vowels are all together, and (iii) there are always 4 letters between P and S?
Comprehensive Algebra
MCQ
Concept: To find the number of arrangements where two specific items do not appear adjacent to each other, subtract the number of arrangements where they are adjacent from the total number of unrestricted arrangements.
In how many ways can the time-table for Monday be arranged if for this day five lessons are planned: in algebra, geometry, history, geography and literature, provided algebra and geometry do not immediately follow each other?
Comprehensive Algebra
MCQ
Concept: A number is divisible by 4 if the number formed by its last two digits is divisible by 4. Determine the valid choices for the last two places and then fill the remaining positions based on whether repetition is allowed or not.
How many five-digit numbers divisible by 4 can be formed by the digits 1, 2, 3, 4 and 5 if (i) digits can be repeated in the same number? (ii) digits cannot be repeated in the same number?
Comprehensive Algebra
MCQ
Concept: A number is divisible by 6 if it is even (ends in 0, 2, or 4) and its sum of digits is divisible by 3. Select 5 distinct digits out of the 6 available digits such that their sum is divisible by 3, and then arrange them ensuring the last digit is even and the first digit is non-zero.
How many five-digit numbers divisible by 6 can be made with the digits 0, 1, 2, 3, 4 and 5 if the digits cannot be repeated in the same number?
Comprehensive Algebra
MCQ
Concept: A 5-digit telephone number uses the digits 0 through 9, where the first digit can be any digit including 0. When digits are pairwise distinct, the number of ways is given by permutations of 10 available digits taken 5 at a time.
How many five-digit telephone numbers with pairwise distinct digits can be composed?
Comprehensive Algebra
MCQ
Concept: A number is divisible by 25 if its last two digits are 25, 50, 75, or 00. Determine the combinations for the last two digits, then count the possibilities for the remaining initial positions without repeating or allowing zero at the leading position depending on repetition rules.
How many numbers of 5 digits divisible by 25 can be made with the digits 0, 1, 2, 3, 4, 5, 6 and 7?
Comprehensive Algebra
MCQ
Concept: To count arrangements where multiple specific pairs of items are restricted from being together, apply the Principle of Inclusion-Exclusion. Subtract the arrangements where at least one pair is together from the total permutations, and add back the arrangements where both pairs are simultaneously together.
Find the number of arrangements of the letters $a, b, c, d$ in which neither $a, b$ nor $c, d$ come together.
Comprehensive Algebra
MCQ
Concept: Assign the restricted crew members to their required sides first. Then select from the remaining unrestricted crew members to complete each side, and multiply by the permutations of arranging the rowers on both the bow and stroke sides.
A boat is to be manned by eight men, of whom 2 can only row on bow side and 1 can only row on stroke side. In how many ways can the crew be arranged?
Comprehensive Algebra
MCQ
Concept: To arrange items of different categories such that members of each category sit together, treat each nationality group as a single unit. First find the arrangements of the groups, then multiply by the internal permutations of each individual group.
In a dinner party there are 10 Indians, 5 Americans and 5 Englishmen. In how many ways can they be arranged in a row so that all persons of the same nationality sit together?
Comprehensive Algebra
MCQ
Concept: To arrange items such that two specific items are not adjacent (successive), calculate the total unrestricted arrangements of all items and subtract the number of arrangements where the two specified items are placed together as a single unit.
Six papers are set in an examination, 2 of them in mathematics. In how many different orders can the papers be given if two mathematics papers are not successive?
Comprehensive Algebra
MCQ
Concept: When specific identical letters must not be adjacent, use the gap method: arrange all other letters first, then insert the restricted identical letters into the spaces created between and at the ends of the arranged letters.
In how many ways can the letters of the word 'PLANTAIN' be arranged so that the two 'A's do not come together?
Comprehensive Algebra
MCQ
Concept: When items from two groups must alternate and both groups have an equal number of members, determine the distinct starting configurations (consonant first or vowel first) and multiply by the permutations of each group while accounting for duplicate letters.
In how many different ways can the letters of the word 'SALOON' be arranged if the consonants and vowels must occupy alternate places?
Comprehensive Algebra
MCQ
Concept: Calculate total permutations of a multiset of letters. Subtract the arrangements where specified letters are grouped together to find non-adjacent cases. For conditional positions, fix the letters at the specified endpoints and arrange the rest.
How many words can be formed by using the letters of the word 'BHARAT'? How many of these words will not contain B and H together? How many of these start with B and end with T?
Comprehensive Algebra
MCQ
Concept: Use basic factorials for unrestricted permutations, block arrangements for grouped items, gap and unit concepts for partial restrictions, and position-matching for alternating arrangements.
There are nine different books on a shelf; four are red and five are green. In how many different orders is it possible to arrange the books on the shelf if:
(a) there are no restrictions;
(b) the red books must be together and the green books together;
(c) the red books must be together whereas the green books may be, but need not be, together;
(d) the colours must alternate, i.e., no two books of the same colour may be adjacent?
Comprehensive Algebra
MCQ
A straight is a five-card hand containing consecutive values. Find (i) how many different straights there are, and (ii) how many straights there are if the cards are not all from the same suit.
Comprehensive Algebra
MCQ
$n$ different objects are arranged in a row. In how many ways can $3$ objects be selected so that (i) all three objects are consecutive, and (ii) all three objects are not consecutive?
Comprehensive Algebra
MCQ
There are $n$ intermediate stations on a railway line from one terminus to another. In how many ways can the train stop at $3$ of these intermediate stations if (i) all three stations are consecutive, and (ii) at least two of the stations are consecutive?
Comprehensive Algebra
MCQ
Concept: Selection of vertices in a polygon to form triangles with or without common sides.
Triangles are formed from the vertices of an $n$-sided polygon. Find the number of triangles so that (i) at least one side of the triangle coincides with the side of the polygon, and (ii) no side of the triangle coincides with the side of the polygon.
Comprehensive Algebra
MCQ
Concept: Selection of non-adjacent items in a circular arrangement.
There are eight stations on a train route in a circular order. Find the number of selections of $3$ stations such that no two stations are adjacent.
Comprehensive Algebra
MCQ
Concept: Permutations with forbidden adjacent elements (complementary counting).
How many $7$-digit numbers are there such that the digits are distinct integers taken from the set $S = \{1, 2, \dots, 9\}$ and such that the integers $5$ and $6$ do not appear consecutively in either order?