## A company produces a women’s bowling ball that is supposed to weigh exactly 14 pounds. Unfortunately, the company has a problem with the var

Question

A company produces a women’s bowling ball that is supposed to weigh exactly 14 pounds. Unfortunately, the company has a problem with the variability of the weight. In a sample of 11 of the bowling balls the sample standard deviation was found to be 0.71 pounds. Construct a 95% confidence interval for the variance of the bowling ball weight. Assume normality.

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2 weeks 2021-11-22T02:21:19+00:00 1 Answer 0

## Answers ( )

1. Answer:

Step-by-step explanation:

Given : A company produces a women’s bowling ball that is supposed to weigh exactly 14 pounds.

Sample size : n=11

Degree of freedom =n-1=10

Sample standard deviation : s= 0.71 pounds

Significance level for 95% confidence interval :

We assume that the bowling ball weight is normally distributed.

Using chi-square distribution table, the required critical values are :-

Then, the 95% confidence interval for the variance of the bowling ball weight will be :

∴ The 95% confidence interval for the variance of the bowling ball weight will be :