Question

2. Lucy wants to become a firefighter. She must pass both a physical and a written. The
probability of passing the physical is 0.75 and once she passes the physical the
probability of passing the written is 0.5.
a. What is the probability that Lucy passes both ?
b. What is the probability that Lucy fails the written if she has already passed the
physical?

Answer 1

Let us denote the events

A : Lucy pass the physical test

B : Lucy pass the written test

Given

Now,

a) The probability that Lucy passes both

b) The probability that Lucy fails the written if she has already passed the physical