The manager of a Spiffy Lube auto lubrication shop is trying to revise his policy on ordering grease gun cartridges. Currently, he orders 110 cartridges per week, but he runs out of cartridges 1 out of every 4 weeks. He knows that, on average, the shop uses 95 cartridges per week. He is also willing to assume that demand for cartridges is normally distributed. (a) What is the standard deviation of this distribution? (b) If the manager wants to order enough cartridges so that his probability of running out during any week is no greater than 0.2, how many cartridges should he order per week?

The manager of a Spiffy Lube auto lubrication shop is trying to revise his policy on ordering grease gun cartridges. Currently, he orders 110 cartridges per week, but he runs out of cartridges 1 out of every 4 weeks. He knows that, on average, the shop uses 95 cartridges per week. He is also willing to assume that demand for cartridges is normally distributed. (a) What is the standard deviation of this distribution? (b) If the manager wants to order enough cartridges so that his probability of running out during any week is no greater than 0.2, how many cartridges should he order per week?

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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A hiring company claims that the variance of the annual salaries for managers is greater in Florida than Georgia. You select a sample of 28 managers in Florida and find the standard deviation to be $11,000. You select a sample of 24 managers in Georgia and find the standard deviation to be $9,200. At α=0.05, can you support the hiring company's claim?
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