A study was conducted in order to estimate μ, the mean number of weekly hours that U. S. adults use computers at home. Suppose a random sample of 81 U. S. adults gives a mean weekly computer usage time of 8.5 hours and that from prior studies, the population standard deviation is assumed to be σ = 3.6 hours. A similar study conducted a year earlier estimated that μ, the mean number of weekly hours that U. S. adults use computers at home, was 8 hours. We would like to test (at the usual significance level of 5%) whether the current study provides significant evidence that this mean has changed since the previous year. Using a 95% confidence interval of (7.7, 9.3), our conclusion is that:

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Ingrid Hines

23 July, 19:20

A study was conducted in order to estimate μ, the mean number of weekly hours that U. S. adults use computers at home. Suppose a random sample of 81 U. S. adults gives a mean weekly computer usage time of 8.5 hours and that from prior studies, the population standard deviation is assumed to be σ = 3.6 hours. A similar study conducted a year earlier estimated that μ, the mean number of weekly hours that U. S. adults use computers at home, was 8 hours. We would like to test (at the usual significance level of 5%) whether the current study provides significant evidence that this mean has changed since the previous year. Using a 95% confidence interval of (7.7, 9.3), our conclusion is that:

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Landin Jarvis · Answer 1

Our conclusion is that the mean number of weekly hours that U. S. adults use computers at home is 8 hours

Explanation:

8 hours falls in the 95% confidence Interval (7.7, 9.3), so we can conclude that the mean weekly hours that U. S. adults use computers at home is 8 hours