A firm has three identical jobs to fill. Only 40% of the candidates in the waiting room are suitable for the job. The personnel director interviews candidates until all three posts are filled. The personnel director spends 40 minutes with each candidate, to determine if he or she is suitable. For those deemed unsuitable, the interview ends there. For those deemed suitable, the director spends an additional 15 minutes discussing the preferences of the candidate. (i) Find the expected value of the time that the total process will take. (ii) Find the variance of the time that the total process will take.

A firm has three identical jobs to fill. Only 40% of the candidates in the waiting room are suitable for the job. The personnel director interviews candidates until all three posts are filled. The personnel director spends 40 minutes with each candidate, to determine if he or she is suitable. For those deemed unsuitable, the interview ends there. For those deemed suitable, the director spends an additional 15 minutes discussing the preferences of the candidate. (i) Find the expected value of the time that the total process will take. (ii) Find the variance of the time that the total process will take.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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