A questionnaire about study habits was given to a random sample of high school students. The...
A questionnaire about study habits was given to a random sample of high school students. The sample of 20 students reported that they spent an average of 215 minutes per week studying with a standard deviation of 70 minutes. What is your 95% confidence interval on the population variance?
Homework Answers
We know, 
~ 
Thus, 95% C.I. of the population variance is:
[
,
], where, 
= 
= 490, n
= 20, 
= 8.91, 
= 32.9
= [282.9787, 1044.8934]. (Ans).
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