3. The amount of time that a drive-through bank teller spends on a customer is a random variable with a mean 3.2 minutes and a standard deviation of 1.6 minutes. If a random sample of 64 customers is observed, find the probability that their mean time at the teller’s window is: a. at most 2.7 minutes; b. more than 3.5 minutes; c. at least 3.5 minutes but less than 3.4 minutes.

3. The amount of time that a drive-through bank teller spends on a customer is a random variable with a mean 3.2 minutes and a standard deviation of 1.6 minutes. If a random sample of 64 customers is observed, find the probability that their mean time at the teller’s window is: a. at most 2.7 minutes; b. more than 3.5 minutes; c. at least 3.5 minutes but less than 3.4 minutes.

Engineering Fundamentals: An Introduction to Engineering (MindTap Course List)

5th Edition

ISBN:9781305084766

Author:Saeed Moaveni

Publisher:Saeed Moaveni

Chapter19: Probability And Statistics In Engineering

Section: Chapter Questions

Problem 48P: You are to write down on a piece of paper the number of credits you are taking this semester. Your...

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