12.34 Screening job applicants. A company retains a psychologist to assess whether job applicants are suited for assembly-line work. The psychologist classifies applicants as one of A (well suited), B (marginal), or C (not suited). The company is concerned about the event D that an employee leaves the company within a year of being hired. Data on all people hired in the past five years give these probabilities:

Question

P(A) = 0.4 P(B) = 0.3 P(C) = 0.3
P(A and D) = 0.1 P(B and D) = 0.1 P(C and D) = 0.2

What is P(D), the probability that an employee leaves within a year?
I am not sure if I just add up all of the intersections to get .4, or do I take (.4*.1) + (.3*.1) + (.3*.2)=.13?

Answer 1

.1 + .1 + .2 = .4

Answer 2

Thank you!

Answer 3

Welcome!