In a group of 800 people, 3/5 play at least one instrument, 96 play two or more. What is the probability that one student play exactly one instrument?  Choose the correct choice.
A) 2 / 125 B) 12 / 25 C) 2 / 25 D) 3 / 25 E) 1 / 5

Rationale: p ( playing 2 or more instruments ) = 96 / 800 = 3 / 25 . then , the probability of playing exactly one instrument is given by : p ( playing 1 or more instruments ) - p ( playing 2 or more instruments ) = 3 / 5 - 3 / 25 = 12 / 25 . answer b .
Answer: B