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

Product of any n consecutive positive integers is divisible by

• n A
• √n B
• n! C
• None D

The key for opening a door is in a bunch of 10 keys. A man attempts to open the door by trying the keys at random discarding the wrong key. The probability that the door is opened in the 5th trial is

• 1 / 10 A
• 2 / 10 B
• 3 / 10 C
• 4 / 10 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

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

• 400 A
• 472 B
• 563 C
• 264 D

• 
  A
• 
  B
• 
  C
• 
  D

An unbiased die is thrown. Then the probability of getting a prime is

• 1/2 A
• 2/3 B
• 3/4 C
• None of these 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 combinations of 10 different objects taken 8 objects at a time is

• 90 A
• 45 B
• 55 C
• 50 D

nCn-r is equal to

• n! A
• n-1Cr B
• nCr C
• None of these D

Number of selections of n different things out of n

• 1 A
• nPr B
• n! C
• nPr D

Out of 40 consecutive natural numbers, two are chosen at random. Probability that the sum of the numbers is odd, is

• 14 / 29 A
• 20 / 39 B
• 1 / 2 C
• n 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

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

How many necklaces can be made from 6 beads of different colours?

• 120 A
• 60 B
• 24 C
• 15 D

• 0 A
• 20 B
• 90 C
• 80 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

Eight chairs are numbered 1 to 8. Two women and three men wish to occupy one chair each. First, the women choose the chairs from amongst the chairs marked 1 to 4 and then the men select the chairs from amongst the remaining. The number of possible arrangement is

• ⁶C₃x ⁴C₂ A
• ⁴C₂x ⁴P₃ B
• ⁴P₂x ⁶P₃ C
• None of these D

• 
  A
• 
  B
• 
  C
• 
  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

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

What is the probability of being born on Wednesday?

• 1/7 A
• 1/2 B
• 1/3 C
• 1/8 D

The number of permutation that can be formed from the letters of the word OBJECT is

• 700 A
• 600 B
• 720 C
• 620 D

The probability that the sum of dots appearing in two successive thrown of two dice, in every time 7 is

• 1/5 A
• 1/36 B
• 1/7 C
• 1/63 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

• 
  A
• 
  B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C
• 
  D

A dice is rolled. The probability that the dots on the top are greater than 4 is

• 1/6 A
• 1/3 B
• 1/2 C
• 1 D

The factorial of a positive integers is a (an)

• Rational number A
• Positive integer B
• Real number C
• None 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

• 0.9 A
• 0.74 B
• 0.2016 C
• None of these D