A medical researcher wants to estimate the average decrease in cholesterol following treatment with a new drug. They obtain a random sample of 400 subjects with high cholesterol using the new drug. The average decrease in cholesterol level is  = 90 and the researcher knows that the decrease in cholesterol has a standard deviation s= 30. Construct a 95% confidence interval for m to estimate the average decrease in cholesterol in the population. (

Q: Find the value of t a/2 for a 99% confidence interval when the sample size is 30

A: Given Confidence = 99% n=30

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Q: find the t/α2 value for a 98% confidence interval for the mean when the sample size is 39.  t/α2=

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Q: Beth wants to determine a 95 percent confidence interval for the true proportion p of high school…

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