Question

In a sample of 50 households, the mean number of hours spent on social networking sites during the month of January was 45 hours. In a much larger study, the standard deviation was determined to be 8 hours. Assume the population standard deviation is the same. What is the 95% confidence interval for the mean hours devoted to social networking in January?

Answer 1

here are the answer choices
The 95% confidence interval ranges from 8 to 45 hours.
The 95% confidence interval ranges from 40.13 to 45.78 hours.
The 95% confidence interval ranges from 43.87 to 46.13 hours.
The 95% confidence interval ranges from 42.78 to 47.22 hours.