Question

The probability of choosing a quarterback from the football team is 1/15. The probability of choosing a quarterback and pitcher is 1/315. What is the probability of choosing a pitcher?

Answer 1

Assuming the choice of either quarterback
`(Q)` or pitcher
`(P)` is independent of one another, you have


`\mathbb P(Q\cap P)=\mathbb P(Q)\mathbb P(P)`

`\frac1{315}=(\mathbb P(P))/(15)`

`\implies\mathbb P(P)=(15)/(315)=\frac1{21}`