Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.3. (Round your answers to four decimal places.)In USE SALT(a) If the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?(b) What is the (approximate) probability that the sample mean hardness for a random sample of 38 pins is at least 51?

Let X be the random variable from normal distribution with mean (μ) = 50, standard deviation (σ) =…

Answered: n USE SALT (a) If the distribution is…

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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n USE SALT (a) If the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51? (b) What is the (approximate) probability that the sample mean hardness for a random sample of 38 pins is at least 51?