Statistics
posted by Zenna .
A group of statistics students decided to conduct a survey at their university to find the average (mean) amount of time students spent studying per week. Assuming a standard deviation of 6 hours, what is the required sample size if the error is to be less than ½ hour with a 95% level of confidence?

First find the allowed standard deviation for the sample average. Then find the number of members of the group to needed reduce the standard deviation to that value.

What is the standard deviation of the following data? If necessary, round your answer to two decimal places.13, 11, 4, 5, 6, 9, 10, 12, 15, 16

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