A researcher surveys 25 people and finds that their average commute is 15 minutes with a standard deviation of 1.5 minutes. Calculate the 95 percent confidence interval on variance. Do most people have a commute of 20 minutes?(adsbygoogle = window.adsbygoogle || []).push({});

Confidence interval for variance? should I just use the variance instead of the standard deviation? so 1.5^2=2.25

root 25= 5

15+1.962.255 and 15−1.962.255

15+0.882 and 15−0.882

15.88,14.12

so, no , most people will not have a commute of 20 minutes

Is this right?

Thanks!

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# How to find Confidence interval

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