# Statistics

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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?

• Statistics -

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.

• Statistics -

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

• Statistics -

393

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