1 Joey has applied for a job with Facebook As part of the hi

1. Joey has applied for a job with Facebook. As part of the hiring process, Facebook will of course look at her grade in BUS 190 at SJSU. If Mina gets an A, theres a 65% chance that Facebook will hire her. But if she does not get an A, theres only a 10% chance that they will hire her. Theres an 80% chance that Mina will get an A in BUS 190.

a. What is the probability that Facebook will hire Mina?

b. It turns out that Facebook does hire Mina. What is the probability that she got an A in BUS 190?

Please show work. Thank you!

Solution

a)

P(hire) = P(A) P(hire|A) + P(not A) P(hire|not A)

= 0.65(0.80) + (1-0.80)(0.10)

P(hire) = 0.54 [answer]

***************

b)

P(A|hire) = P(A and hire) / P(hire)

As

P(A and hire) = P(A) P(hire|A) = 0.65(0.80) = 0.52

Then

P(A|hire) = 0.52/0.54 = 0.96296 [ANSWER]