The amount of time taken by a bank teller to serve randomly arriving customers has a normal distribution with a mean of 2.5 minutes and a standard deviation of 30 seconds. (a) For two of the customers, what is the probability that both are served in 2 minute or less? (b) If four customers are served, what is the probability that at least one of them have serving time that exceeds 3 minutes?

The amount of time taken by a bank teller to serve randomly arriving customers has a normal distribution with a mean of 2.5 minutes and a standard deviation of 30 seconds. (a) For two of the customers, what is the probability that both are served in 2 minute or less? (b) If four customers are served, what is the probability that at least one of them have serving time that exceeds 3 minutes?

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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