The surnames of 40 children in a class arranged in alphabetical order. 16 of the surnames begins with O and 9 of the surname begins with A, 14, of the letters of the alphabet, do not appear as the first letter of a surname

What is the probability that the surname of a child picked at random from the class begins with either O or A?

A. 5/8
B. 7/8
C. 9/16
D. 14/25
E. 39/40

Correct Answer: Option A

A. 5/8

Explanation
No. of possible outcome = 40
No. of expected outcome = 16 + 9 = 25
Probability = 25/40 = 5/8