The breaking strength (in kg/mm) for a certain type of fabric has mean 1.86 and standard deviation 0.27. A random sample of 80 pieces of fabric is drawn. (i). What is the probability that the sample mean breaking strength is less than 1.8 kg/mm? . (ii). How large a sample size is needed so that the probability of the sample mean being less than 1.8 will be 0.01? .

The breaking strength (in kg/mm) for a certain type of fabric has mean 1.86 and standard deviation 0.27. A random sample of 80 pieces of fabric is drawn. (i). What is the probability that the sample mean breaking strength is less than 1.8 kg/mm? . (ii). How large a sample size is needed so that the probability of the sample mean being less than 1.8 will be 0.01? .

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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