# AP Statistics

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A school psychologist reports that the mean number of hours the students at this school sleep each night is 8 hours. The students believe the mean is not 8 hours. To find an estimate of the true mean, they select a random sample of 15 students from their school and ask how many hours each slept last night. A stemplot and boxplot of the numbers of hours are shown here. t he sample mean is 6.67 hours with a sample standard deviation of 1.88 hours.
a. Verify that the conditions for computing a confidence interval are met in this case.

b. Compute and interpret a 95% confidence interval for the mean number of hours the students at this school sleep each night.

• AP Statistics -

A school psychologist reports that the mean number of hours the students at this school sleep each night is 8 hours. The students believe the mean is not 8 hours. To find an estimate of the true mean, they select a random sample of 15 students from their school and ask how many hours each slept last night. A stemplot and boxplot of the numbers of hours are shown here. T he sample mean is 6.67 hours with a sample standard deviation of 1.88 hours.
a. Verify that the conditions for computing a confidence interval are met in this case.
b. Compute and interpret a 95% confidence interval for the mean number of hours the students at this school sleep each night.

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