A soft-drink machine is regulated so that the amount of drink dispensed averages 240 milliliters with a standard deviation of 15 milliliters. Periodically, the machine is checked by taking a sample of 40 drinks and computing the average content. If the mean of the 40 drinks is a value within 2 standard deviations from the mean , the machine is thought to be operating satisfactorily; otherwise, adjustments are made. If the company official found the mean of 40 drinks to be 236 milliliters and concluded that the machine needed no adjustment. Was this a reasonable decision?

A soft-drink machine is regulated so that the amount of drink dispensed averages 240 milliliters with a standard deviation of 15 milliliters. Periodically, the machine is checked by taking a sample of 40 drinks and computing the average content. If the mean of the 40 drinks is a value within 2 standard deviations from the mean , the machine is thought to be operating satisfactorily; otherwise, adjustments are made. If the company official found the mean of 40 drinks to be 236 milliliters and concluded that the machine needed no adjustment. Was this a reasonable decision?

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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