Okay folks I have two others that are stumping me
You intend to estimate a population mean with a confidence interval. You believe the population to have a normal distribution. Your sample size is 26.
Find the critical value that corresponds to a confidence level of 98%.
ta/2 = ±
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You want to obtain a sample to estimate a population proportion. At this point in time, you have no reasonable estimate for the population proportion. You would like to be 99.9% confident that you estimate is within 0.1% of the true population proportion. How large of a sample size is required?