A college student wanted to estimate the average amount of time spent texting each day among college students. He randomly sampled 174174 college students and asked them to keep track of how many minutes they spent texting(reading and writingtexts) on a certain day. The average time spent texting in one day for the 174 in the study was 118 minutes. Suppose sigma Subscript Upper XσX is known to be 60 minutes. Assume all conditions are satisfied for inference to all college students.
- Construct a 99% confidence interval for mu Subscript Upper XμX, the average time spent texting among all college students
- What is the value of the lower bound of the confidence interval?
- What is the value of the upper bound of the confidence interval?