Question 1: A researcher would like to estimate the true meannumber of hours adults sleep at night. Suppose that populationsleep time is known to follow a Normal distribution with standarddeviation as 1.5 hours. The researcher random select 100 people andfound the average sleeping hours for the sample of 100 people is6.5 hours.
1) Use this sample mean to estimate the true population mean ofsleep time with 95% confidence. (hint: 95% CI)
2) If the researcher intends to increase the confidence of theestimation to 99%, what is the CI now. Compare the 99% CI with the95% CI calculated in previous question, what has been changed?
3) If the researcher wants to increase the confidence ofestimation to 99% without extend the margin of error, what shouldthis researcher do? (hint: sample size)
4) Reflect on previous questions and the CI formula , whatfactors can affect the CI and how?
