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OpenStax, Statistics §7.1 The Central Limit Theorem for Sample Means (Averages) · Example 5 · Statistics · Sampling distributions

The Central Limit Theorem for Sample Means (Averages) · Example 5

The mean number of minutes for app engagement by a tablet user is 8.2 minutes. Suppose the standard deviation is one minute. Take a sample of 60.

(a) What are the mean and standard deviation for the sample mean number of app engagement minutes by a tablet user?
(b) What is the standard error of the mean?
(c) Find the 90^th percentile for the sample mean time for app engagement for a tablet user. Interpret this value in a complete sentence.
(d) Find the probability that the sample mean is between eight minutes and 8.5 minutes.

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OpenStax, Statistics · §7.1 The Central Limit Theorem for Sample Means (Averages) · Example 5

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