21. The mean BMI from a random sample of 30 men is 31.3 with standard deviation...

21. The mean BMI from a random sample of 30 men is 31.3 with standard deviation ? = 4.6. Suppose the distribution of BMI is approximately normal. Construct a 95% confidence interval of the population mean BMI.

22. (5 Points) A medical researcher wants to investigate the amount of time it takes for patients' headache pain to be relieved after taking a new prescription painkiller. She believes that the population is normally distributed with a standard deviation of σ = 21 minutes. From a sample of 120 patients, the mean time to relieve their headaches was 63 minutes. Construct a 90% confidence interval of the population mean time.

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orchestra answered 2 years ago

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