A sample of 12 concrete specimens from supplier Awere tested for their compressive strength. The resultsgave an average of 85 MPa and a standard deviationof 4 MPa. From supplier B, 10 specimens weresimilarly tested and gave an average compressivestrength of 81 MPa and a standard deviation of 5 MPa.(a) Using procedures of Hypothesis Testing, can weconclude at the 0.05 level of significance that thecompressive strength of concrete from Aexceeds that from B by more than 2 MPa? Assume thepopulations to be approximately normal withequal variances.(b) Is the assumption of equal variances in (a)justifiable at an a = 0.10?

Given Information: Sample A: n1=12 x¯1=85 s1=4 Sample B: n2=10 x¯2=81 s2=5

Answered: A sample of 12 concrete specimens from…

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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