H0 : sigma = 2.5
Ha: sigma > 2.5
test statsitics:
n = 41, s = 2.9
chi^2 = (n-1)s^2/sigma^2
= ((41-1) *2.9^2)/2.5^2
= 53.824
p value = 1 - P(chi^2 < 53.824) with df= 40
P value = 0.0709
As p value > 0.01 Fail to reject H0 There is not suffiicient
evidence to support the claim that the std. deviation is greater
than 2.5 inches
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