You are an industrial and organizational psychologist in an international company. Recently, the company is organizing a job fair. In order to attract candidates to come for the interview, your boss asked you to provide career advice at the job fair and to select a test for those who apply for the post.

At the end of the job fair, the personnel manager interviewed 50 candidates applying for the post of junior marketing manager, and 5 are hired.

a. Suppose the base rate for success on the job post is 0.6, and the test that you chose for the job fair is with 0.4 validity. Based on the given information, what is the selection ratio of the post?

b. How many of the candidates selected on the basis of the test would be expected to succeed on the job?