Problem 1. The Rockwell hardness of a metal is determined by impressing ahardened point into the surface of the metal and then measuring the depth of penetration of the point. Suppose the Rockwell hardness of a particular alloy is normallydistributed with mean 70 and standard deviation 3. (Rockwell hardness is measuredon a continuous scale.)a) If a specimen is acceptable only if its hardness is between 67 and 75, what isthe probability that a randomly chosen specimen has an acceptable hardness?b) If two alloys are randomly selected, which is the probability that one will haveRockwell hardness more that 50 and one no more than 75?c) Within what limits would you expect. the Rockwell hardness to lie, with prob-ability .98?

Given: Mean = 70 Standard deviation = 3

Answered: Problem 1. The Rockwell hardness of a…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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