ECAT Pre Engineering MCQ Test With Answer for Chapter 9 Mathematics

The probability that a slip of number divisible by 4 is picked from the slips bearing numbers 1, 2, 3, ...10 is

• 1/5 A
• 1/4 B
• 1/3 C
• 1/2 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

A bag contains 5 white, 7 red and 5 black balls. If four balls are drawn one by one with replacement, the probability that none is white is

• (11/16)² A
• (5/16)² B
• (11/16)⁴ C
• (5/16)⁴ D

If 4 ⁶P_r= ⁶P_r+1, then r is equal to

• 4 A
• 3 B
• 2 C
• 1 D

What is the probability of being born on Wednesday?

• 1/7 A
• 1/2 B
• 1/3 C
• 1/8 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

In school there are 150 students Out of these 80 students enrolled for mathematics class 50 enrolled for English class and 60 enrolled for Physics class The student enrolled for English cannot attend any other class but the students of mathematics and Physics can take two courses at a time Find the number of students who have taken both physics and mathematics.

• 40 A
• 30 B
• 50 C
• 20 D

Arithmetic mean between 14 and 18 is

• 16 A
• 17 B
• 15 C
• 32 D

• 
  A
• 
  B
• 
  C
• 
  D

Product of any n consecutive positive integers is divisible by

• n A
• √n B
• n! C
• None 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

• 0 A
• -1 B
• 1 C
• 2 D

• 3 A
• 6 B
• 0 C
• None of these D

Three integers are chosen at random from the first 20 integers. Then probability that their product is even, is

• 2 / 19 A
• 3 / 29 B
• 17 / 19 C
• 4 / 19 D

The domain of a finite sequence is a

• Set of natural numbers A
• R B
• Subset of N C
• Proper subset of N D

The probability that a slip of numbers divisible by 4 is picked from the slips of number 1,2,3,4,......10 is

• 1/5 A
• 2/5 B
• 1/10 C
• 3/10 D

A sequence is a function whose domain is

• N A
• Subset of N B
• R C
• None of these D

The number of significant numbers which can be formed by using any number of the digits 0, 1, 2, 3, 4 but using each not more than once in each number is

• 260 A
• 356 B
• 410 C
• 96 D

A box contains 10 red 30 white and 20 black marbles When a marble is drawn at random the probability that it is either red or white is

• 1/6 A
• 1/3 B
• 1/2 C
• 2/3 D

• 
  A
• 
  B
• 
  C
• 
  D

A committee consists of 9 experts taken from three institutions A, B, and C, of which 2 are from, A, 3 form B and 4 from C. If three experts resign, then the probability that they belong to different institutions is

• 1 / 729 A
• 1 / 24 B
• 1 / 21 C
• 2 / 7 D

• 
  A
• 
  B
• 
  C
• 
  D

The probability that a person A will be alive 15 years hence is 5/7 and the probability that another person B will be alive 15 years hence is 7/9. Find the probability that both will be alive 15 years hence

• 4/63 A
• 5/9 B
• 45/49 C
• None of these D

• 56 A
• 7 B
• 8 C
• 8/7 D

How many signals can be given by 5 flags of different colours, using 3 flags at a time

• 120 A
• 60 B
• 24 C
• 15 D

Five engineering, four mathematics, two chemistry books are placed on a table at random.The probability that the books of each kind are all together is

• 
  A
• 
  B
• 
  C
• 
  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

• 120 A
• 5 B
• 4 C
• 6 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

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