ECAT Pre Engineering MCQ Test With Answer for Chapter 9 Mathematics

The sample space for tossing a coin twice is

• {H, T} A
• {HH, HT, TH, TT} B
• {H, T, HH} C
• {HH, HT, TT} D

• 8 A
• 1/56 B
• 56 C
• None of these 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

In a class of 100 students, 60 drink tea, 50 drink coffee and 30 drink both. A student from his class is selected at takes at last one of 2 drinks is

• 2 / 5 A
• 3 / 5 B
• 4 / 5 C
• None of these D

• 0 A
• 20 B
• 90 C
• 80 D

• 56 A
• 7 B
• 8 C
• 8/7 D

A die is thrown 100 times. If getting an odd number is considered a success, the variance of the number of successes is

• 50 A
• 25 B
• 10 C
• 100 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

Which one is not defined∀n∈Z+

• -n! A
• n! B
• (-n)! C
• n!+0!=n!+1 D

If A is an event then which of the following is true

• P(A)<0 A
• 0≥P(A)≤1 B
• P(A)>0 C
• None D

Two coins are tossed twice each. The probability that the head appears on the first toss and the same forces appear in the two tosses is

• 1/4 A
• 1/2 B
• 1/3 C
• 1/7 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

20. 19. 18. 17= _______

• 
  A
• 
  B
• 
  C
• 
  D

Arithmetic mean between 14 and 18 is

• 16 A
• 17 B
• 15 C
• 32 D

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

• 
  A
• 
  B
• 
  C
• 
  D

If n is a negative integer n! is

• 1 A
• 0 B
• Unique C
• Not defined D

The sum of all odd numbers between 100 and 200 is

• 6200 A
• 7500 B
• 6500 C
• 3750 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

Three dice are thrown together. The probability of getting a total of at least 6 is

• 103 / 108 A
• 10 / 216 B
• 93 / 108 C
• None of these D

• 
  A
• 
  B
• 
  C
• 
  D

9. 8. 7. 6= ______

• 
  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

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

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

A sequence is a function whose domain is

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

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

• 120 A
• 60 B
• 24 C
• 15 D

Four cards are drawn at random from a pack of 52 playing cards. The probability of getting all the four cars of the same suit is

• 44/4165 A
• 22/4165 B
• 11/4165 C
• None of these D

The factorial of a positive integers is a (an)

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

The probability to get an odd number in a dice thrown once is

• 6 A
• 1 B
• 1/6 C
• 1/2 D

Product of any n consecutive positive integers is divisible by

• n A
• √n B
• n! C
• None D