An Internet provider contacts a random sample of 225 customers and asks how many hours per week the customers use the Internet. The average amount of time spent on the Internet per week was 7.2 hours, with a standard deviation of 3.8 hours. a) What is the degree of freedom? b) Use StatKey to find t* with a 95% confidence level. c) Construct a 95% confidence interval for the average amount of time customers of this Internet provider spend on the Internet each week. Round the margin of error to two decimal places. (Round your answer to two decimal places) d) Interpret your interval in the context of this situation.
Added by Jesse P.
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In this case, the sample size is 225, so the degree of freedom is 225 - 1 = 224. Show more…
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