Question

In a sample of 200 households, the mean number of hours spent on social networking sites during the month of January was 55 hours. In a much larger study, the standard deviation was determined to be 7 hours. Assume the population standard deviation is the same. What is the 99% confidence interval for the mean hours devoted to social networking in January?

Answer 1

Any choices?

Answer 2

The 99% confidence interval ranges from 53.73 to 56.27 hours.
The 99% confidence interval ranges from 7 to 55 hours.
The 99% confidence interval ranges from 54.51 to 55.49.
The 99% confidence interval ranges from 55 to 60 hours.

Answer 3

D

Answer 4

I medal and fan

Answer 5

How did u get that

Answer 6

The 99% confidence interval ranges from 55 to 60 hours.

Answer 7

Thanks :)

Answer 8

Thanks sorry I didn't explain I have to go :l

Answer 9

Its fine

Answer 10

I was wrong but that fine

Answer 11

it*