Question

Explain how you would solve this problem. In the short answer section write out all five steps in hypothesis testing you use to solve this problem.

According to a recent report, adults spend an average of 170 minutes on the smart phones each day. A certain statistics instructor believe students at WCC spend more time, on average, on their phones per day.

To test his hypothesis the statistics teacher samples 25 students to find out how many minutes per day they spent on their smart phones. The resulting data was as followed (in minutes):

170	167	174	179	179	187	179	183	179
156	163	156	187	156	167	156	174	170
183	179	174	179	170	159	187

Test the statistics instructors hypothesis (that students spend more than 170 minutes on their phone per day, on average) at the 0.05 level of significance.

Answer 1

First enter Data into EXCEL

We have to find the sample mean.

Excel command is =AVERAGE(Select data)

sample mean =

Now we have to find sample standard deviation.

Excel command is =STDEV(Select data)

standard deviation = s = 10.312

n = 25

S =10.312

claim : The students spend more than 170 minutes on their phone per day, on average

Null and alternative hypothesis is

H0 : u = 170

H1 : u 170

Level of significance = 0.05

Here population standard deviation is not known so we use t-test statistic.

Test statistic is

Degrees of freedom = n - 1 = 25 -1 = 24

P-value = 0.1168 ( using t table)

P-value ,Failed to Reject H0

conclusion : There is insufficient evidence to conclude that the students spend more than 170 minutes on their phone per day, on average