Exercise 2. Rockwell hardness of pins of a certain type is known to have a mean valueof 50 and a standard deviation of 1.2.a. If the distribution is normal, what is the probability that the sample mean hardnessfor a random sample of 9 pins is at least 51?b. Without assuming population normality, what is the (approximate) probabilitythat the sample mean hardness for a random sample of 40 pins is at least 51?

From the provided information, Mean (µ) = 50 Standard deviation (σ) = 1.2 X~N (50, 1.2)

Answered: Exercise 2. Rockwell hardness of pins…

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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