The weights of packets of chips are known to be distributed with a variance of 2.56 grams. A sample of 100 packs were tested and the mean weight was 24.1 grams.
Calculate a confidence interval for the population mean .
A sample of the heights of people from a population resulted in a sample mean of meters. Given that the standard deviation, , is known, which of the following represents a confidence interval for the population mean?
The number of hours students spend on homework each week is known to be distributed with a standard deviation of 3.21 hours. A sample of 50 students were asked how many hours they spend doing homework in a week and the results are given in the table.
Find the sample mean.
Calculate a confidence interval for the population mean.