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Q1:

2025 Slot 1

Permutation & Combination

Medium

A cafeteria offers 5 types of sandwiches. Moreover, for each type of sandwich, a customer can choose one of 4 breads and opt for either small or large sized sandwich. Optionally, the customer may also add up to 2 out of 6 available sauces. The number of different ways in which an order can be placed for a sandwich, is

Answer options
Option 1
Correct Answer
Explanation for 2025 Slot 1 QA question 1

Q3:

CAT 2024 Slot 2

Permutation & Combination

Hard

P, Q, R and S are four towns. One can travel between P and Q along 3 direct paths, between Q and S along 4 direct paths, and between P and R along 4 direct paths. There is no direct path between P and S, while there are few direct paths between Q and R, and between R and S. One can travel from P to S either via Q, or via R, or via Q followed by R, respectively, in exactly 62 possible ways. One can also travel from Q to R either directly, or via P, or via S, in exactly 27 possible ways. Then, the number of direct paths between Q and R is

Q4:

CAT 2024 Slot 1

Permutation & Combination

Medium

The sum of all four-digit numbers that can be formed with the distinct non-zero digits a,b,c,a, b, c, and dd, with each digit appearing exactly once in every number, is 153310+n153310 + n, where nn is a single digit natural number. Then, the value of (a+b+c+d+n)(a + b + c + d + n) is

Q5:

CAT 2023 Slot 1

Permutation & Combination

Medium

The number of all natural numbers up to 10001000 with non-repeating digits is

Answer options
Option 1
Correct Answer
Explanation for CAT 2023 Slot 1 QA question 5

Q6:

CAT 2022 Slot 3

Permutation & Combination

Medium

The arithmetic mean of all the distinct numbers that can be obtained by rearranging the digits in 14211421, including itself, is

Answer options
Option 4
Correct Answer
Explanation for CAT 2022 Slot 3 QA question 6

Q7:

CAT 2022 Slot 2

Permutation & Combination

Medium

The number of integers greater than 20002000 that can be formed with the digits 0,1,2,3,4,50, 1, 2, 3, 4, 5, using each digit at most once, is

Answer options
Option 3
Correct Answer
Explanation for CAT 2022 Slot 2 QA question 7

Q8:

CAT 2022 Slot 1

Permutation & Combination

Medium

The number of ways of distributing 2020 identical balloons among 44 children such that each child gets some balloons but no child gets an odd number of balloons, is

Q9:

CAT 2021 Slot 3

Permutation & Combination

Medium

A four-digit number is formed by using only the digits 11, 22 and 33 such that both 22 and 33 appear at least once. The number of all such four-digit numbers is

Q10:

CAT 2021 Slot 2

Permutation & Combination

Medium

The number of ways of distributing 1515 identical balloons, 66 identical pencils and 33 identical erasers among 33 children, such that each child gets at least four balloons and one pencil, is

Q11:

CAT 2021 Slot 1

Permutation & Combination

Medium

The number of groups of three or more distinct numbers that can be chosen from 1,2, 3,4,5,6,73,4,5,6,7 and 88 so that the groups always include 33 and 55, while 77 and 88 are never included together is

Q12:

CAT 2020 Slot 3

Permutation & Combination

Easy

How many integers in the set (100,101,102,…,999)(100,101,102, \ldots, 999) have at least one digit repeated?

Q13:

CAT 2020 Slot 2

Permutation & Combination

Hard

How many 44-digit numbers, each greater than 10001000 and each having all four digits distinct, are there with 77 coming before 3?

Q14:

CAT 2019 Slot 1

Permutation & Combination

Medium

With rectangular axes of coordinates, the number of paths from (1,1)(1,1) to (8,10)(8,10) via (4,6)(4,6), where each step from any point (x,y)(x, y) is either to (x(x, y+1)y+1) or to ( x+1,yx+1, y ), is

Q15:

CAT 2018 Slot 2

Permutation & Combination

Medium

In a tournament, there are 4343 junior level and 5151 senior level participants. Each pair of juniors play one match. Each pair of seniors play one match. There is no junior versus senior match. The number of girl versus girl matches in junior level is 153153, while the number of boy versus boy matches in senior level is 276276. The number of matches a boy plays against a girl is

Q16:

CAT 2018 Slot 1

Permutation & Combination

Medium

How many numbers with two or more digits can be formed with the digits 1,2,3,4,5,6,7,8,9,1,2,3,4,5,6,7,8,9, so that in every such number, each digit is used at most once and the digits appear in the ascending order?

Q17:

CAT 2017 Slot 2

Permutation & Combination

Easy

In how many ways can 88 identical pens be distributed among Amal, Bimal, and Kamal so that Amal gets at least 11 pen, Bimal gets at least 22 pens, and Kamal gets at least 33 pens?

Q18:

CAT 2017 Slot 2

Permutation & Combination

Hard

How many four digit numbers, which are divisible by 66, can be formed using the digits 0,2,3,4,60, 2, 3, 4, 6, such that no digit is used more than once and 00 does not occur in the left-most position?

Q19:

CAT 2017 Slot 1

Permutation & Combination

Medium

Let AB,CD,EF,GH,AB, CD, EF, GH, and JKJK be five diameters of a circle with center at OO. In how many ways can three points be chosen out of A,B,C,D,E,F,G,H,J,K,A, B, C, D, E, F, G, H, J, K, and OO so as to form a triangle?

Q20:

CAT 2017 Slot 1

Permutation & Combination

Medium

In how many ways can 77 identical erasers be distributed among 44 kids in such a way that each kid gets at least one eraser but nobody gets more than 33 erasers?

Answer options
Option 1
Correct Answer
Explanation for CAT 2017 Slot 1 QA question 20