ECAT Pre Engineering Mathematic MCQ Test With Answer for Chapter 9 (Permutation, Combination and Probability)

The sum if 1,3,5,7,9........ up to 20 terms is

• 400 A
• 472 B
• 563 C
• 264 D

Two unbiased dice are thrown. The probability that the total score is > 5 is

• 1 / 18 A
• 7 / 18 B
• 13 / 18 C
• 11 / 18 D

A die is rolled. What is the probability that the dots on the top are greater than 4?

• 1/4 A
• 1/2 B
• 1/3 C
• 1/33 D

The number of 5-digit number that can be formed from the digits 1,2,4,6,8, when 2 and 8 are never together is

• 72 A
• 48 B
• 144 C
• 20 D

For a positive integer n

• n! = n(n + 1) A
• n! = n(n+1)! B
• n! = n(n - 1 ) C
• n! = n(n - 1)! D

• 1.5 A
• 1.2 B
• 8 C
• None of these D

Number of permutations of n distinct objects taken r(<n - 3) at a time which exclude 3(<n) particular objects is

• 3! P(n, r - 3) A
• P(n, 3) P(n, r - 3) B
• P(r, r)P(n, r - 3) C
• P(n - 3, r) D

n!/(n-1)!=

• n A
• n! B
• (n-1)! C
• 0! D

A class contains nine boys and three girls, in how many ways can the teacher choose a committee of four?

• 60 A
• 460 B
• 495 C
• 272 D

How many different 5-digit even numbers are possible form digit 1,2,4,6,8

• 4 : 4! A
• 4! B
• 5! C
• 4!+4! D

An experiment yields 3 mutually exclusive and exhaustive events A, B, C, if P(A) =2 and P(B) = 3. then P(C) =

• 1 / 11 A
• 2 / 11 B
• 3 / 11 C
• 6 / 11 D

• 0 A
• 20 B
• 90 C
• 80 D

In how many ways can 5 persons be seated at a round table

• 5! A
• 4! B
• 3! C
• 120 D

• 110 A
• 220 B
• 1320 C
• None of these D

Out of 10, 000 families with 4 children each, the number of families all of whose children are daughters is

• 375 A
• 500 B
• 625 C
• 150 D

There are 25 tickets bearing number from 1 to 25. One ticket is drawn at random. The probability that the number on it is a multiple of 5 or 6 is

• 7 / 25 A
• 9 / 25 B
• 11 / 25 C
• None of these D

What is the probability of being born on Wednesday?

• 1/7 A
• 1/2 B
• 1/3 C
• 1/8 D

The number of the diagonals of a 6 sided figure is

• 15 A
• 21 B
• 9 C
• 6 D

A key ring is an example of

• Permutation A
• Circular permutation B
• Combination C
• None D

How many arrangements of the letters of the word MATHEMATICS can be made

• 
  A
• 
  B
• 
  C
• 
  D

A combination lock on a suitcase has 3 wheels each labeled with nine digits from 1 to 9. If an opening combination is a particular sequence of three digits with no repeats, the probability of a person guessing the right combination is

• 1 / 500 A
• 1 / 504 B
• 1 / 252 C
• 1 / 250 D

Six boys and 3 girls are to be seated at random, in a row, for a photograph. The probability that no two girls will sit together is

• 1/12 A
• 1/6 B
• 5/12 C
• 7/12 D

There are 16 point in a plane, in which 6 are collinear. how many lines can be drawn by joining these points?

• 10 A
• 66 B
• 71 C
• 106 D

• P(A) + P(B) A
• P(A) - P(B) B
• P(A) . P(B) C
• P(A) / P(B) D

How many 3 digit numbers can be formed by using each one of the digit 2, 3, 5, 7, 9 only once?

• 15 A
• 24 B
• 60 C
• 120 D

Three numbers are chosen random without replacement from {1, 2, 3, ...., 10}. the probability that minimum of the chosen numbering is 3 or their maximum is 7

• 7 / 40 A
• 5 / 40 B
• 11 / 40 C
• None of these D

For two events A and B if P(A) = P (A/B) = 1/4 and P(B/A) = 1/2, then

• A is sub-event of B A
• A and B are mutually exclusive B
• A and B are independent and P(A/B) = 3/4 C
• None of these D

A card is drawn from a pack of cards numbered 2 to 53. the probability that the number on the card is prime number less than 20 is

• 2 / 13 A
• 4 / 13 B
• 5 / 13 C
• 8 / 13 D

Product of any n consecutive positive integers is divisible by

• n A
• √n B
• n! C
• None D

A box containing 10 mangoes out of which 4 are rotter. Two mangoes are taken together from the box. If one of them is found to be good, the probability that the other is also good is

• 1 / 3 A
• 8 / 15 B
• 5 / 13 C
• 5 / 9 D