ECAT Mathematics Chapter 9 Permutation, Combination and Probability

All letters of the word "AGAIN" are permuted in all possible ways and the words so formed (with or without meaning) are written as in dictionary, then the 50th word is

• NAAGI A
• NAAIG B
• IAANG C
• INAGA D

If A and B are two disjoint events then

• P(A∪B)=P(A)+P(B) A
• P(A∪B)=P(A)-P(A∪B) B
• P(A∪B)=P(A)or P(B) C
• None D

9. 8. 7. 6= ______

• 
  A
• 
  B
• 
  C
• 
  D

The sum of all positive integral multiple of 5 less than 100 is

• 950 A
• 760 B
• 1230 C
• 875 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

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

Form a group of 5 men and 3 women, a committee of 4 persons is to be selected randomly. The probability that there is a majority of men is

• 1/4 A
• 1/3 B
• 1/2 C
• 1/6 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

An integer is chosen at random from the number ranging from 1 to 50. the probability that the integer chosen is a multiple of 2 or 3 or 10 is

• 3 / 10 A
• 5 / 10 B
• 7 / 10 C
• 9 / 10 D

What is the probability of being born on Wednesday?

• 1/7 A
• 1/2 B
• 1/3 C
• 1/8 D

A key ring is an example of

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

A sequence is a function whose domain is

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

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

• 
  A
• 
  B
• 
  C
• 
  D

• 6 A
• 360 B
• 120 C
• 24 D

When a selection of object is made without paying regard to the order of selection, it is called

• Sequence A
• Series B
• Combination C
• Permutation D

The sum of all odd numbers between 100 and 200 is

• 6200 A
• 7500 B
• 6500 C
• 3750 D

The number of permutations of n objects of which there are n₁like of one kind, n₂like of the second kind and n₃like objects of third kind are

• 
  A
• 
  B
• 
  C
• 
  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

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

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

The number of combinations of 10 different objects taken 8 objects at a time is

• 90 A
• 45 B
• 55 C
• 50 D

Fifteen girls compete in a race. The first three places can be taken by them in

• 3! ways A
• 12! ways B
• 15 x 14 x 13 ways C
• 42 ways 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

Number of selections of n different things out of n

• 1 A
• nPr B
• n! C
• nPr D

Arithmetic mean between 14 and 18 is

• 16 A
• 17 B
• 15 C
• 32 D

The sample space for tossing a coin once is

• {T, T} A
• {H, H} B
• {H, T} C
• None of these D

n(n - 1) (n - 2) .... (n - r + 1) = ______

• 
  A
• 
  B
• 
  C
• 
  D

The number of the diagonals of a 6 sided figure is

• 15 A
• 21 B
• 9 C
• 6 D

Given two independent event A and B such that P(A) = 0.30 and P(B) = 0.60. Probability of getting neither A nor B is

• 0.28 A
• 0.13 B
• 0.12 C
• 0.42 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