UGC-NET | UGC NET CS 2016 Aug – II | Question 4

What is the probability that a randomly selected bit string of length 10 is a palindrome?
(A) 1/64
(B) 1/32
(C) 1/8
(D) 1/4

Answer: (B)
Explanation: In the given question we have a palindrome: in even length palindrome half length is fixed and rest is repeated. So, in 10 bit palindrome, we have 5 position to be filled with 2 choices each-

i.e. 2⁵ choices for first half and 2⁵ choices for second half.

Probability = favorable outcome / total outcome
     =  25/ 210
     =  1 / 25
     =  1 / 32.

So, option (B) is correct.

Quiz of this Question