Question

In a class of students, the following data table summarizes how many students play an instrument or a sport. What is the probability that a student who plays a sport also plays an instrument?
Plays an instrument Does not play an instrument
Plays a sport 4 3
Does not play a sport 14 8

Answer 1

We want P(plays instrument | plays sport) = (number who play both)/(number who play a sport) = 4/(4+3) = 4/7 ≈ 0.5714.