# One sample Z test

A Survey is conducted to determine the mean number of minutes per day that teens between the age of 16 and 18 spend watching television per day. A previous study showed that the population standard deviation was 21.5 minutes. The organization selected a random sample of n = 200 teens between the ages of 16 and 18 and recorded the number of minutes of TV that each person watched on a particular day. The mean time was 191.3 minutes. If the leaders of the organization wish to develop an interval estimate with 98 percent confidence, what critical value should be used?

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Critical value

A Survey is conducted to determine the mean number of minutes per day that teens between the age of 16 and 18 spend watching television per day. A previous study showed that the population standard deviation was 21.5 minutes. The organization selected a ...

#### Solution Summary

The solution provides step by step method for the calculation of Z test. . Formula for the calculation and Interpretations of the results are also included. Interactive excel sheet is included. The user can edit the inputs and obtain the complete results for a new set of data.