Posted by Rebecca on .
The mean television viewing time for Americans is 15 hours per week. Suppose a sample of 60 Americans is taken to further investigate viewing habits. Assume the population standard deviation for weekly viewing ime is o = 4 hours.
A What is the probability the sample mean will be within 1 hour of the population mean?
B. What is the probability the sample mean will be within 45 minutes of the population mean?

Statistics 
PsyDAG,
You need to convert the hours to a Z score and then look up the probabilities in the back of your statistics textbook in an appendix labeled something like "areas under the normal distribution."
Z = (X  ƒÊ)/SD, where X = raw score, ƒÊ = mean and SD = standard deviation.
A involves X of 14 to 16, while B involves X of 14.25 to 15.75, converting minutes to portions of an hour.
You should be able to solve it with this information. I hope it helps. Thanks for asking. 
Statistics 
Rebecca,
Just wanted to say thank you for your help. It is greatly appreciated.

Statistics 
Anonymous,
kjjn

Statistics 
Anonymous,
0.38680

Statistics 
Anonymous,
NO IDEA PLZ HELP ME