Let x represent the number of mountain climbers killed each year. The long- term
variance of x is approximately σ2 =136.2. Suppose that for the past 8 years, the variance
has been s = 115.1. Use a 1% level of significance to test the claim that the recent
variance for number of mountain-climber deaths is less than 136.2.
Null hypothesis "H_0:\\sigma^2=136.2."
Alternative hypothesis "H_a:\\sigma^2<136.2."
Tests statistic: "\\chi^2=\\frac{(n-1)s^2}{\\sigma^2}=\\frac{(8-1)*115.1}{136.2)}=5.92."
Degrees of freedom: "df=n-1=8-1=7."
P-value: "p=P(\\chi^2<5.92)=" 0.4509.
Since the p-value is greater than 0.01, fail to reject the null hypothesis.
There is no sufficient evidence that the recent variance for number of mountain-climber deaths is less than 136.2.
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