In research on cell phone use by teenagers it was found that the average connect time for a call was at least 15 minutes.Social psychologists feel that this study understated the time.To determine this claim,cell phone bills for 15 teenagers were evaluated.On average,the time spent was 18.5 minutes with a sample standard deviation of four minutes (assume a normal distribution).Calculate the appropriate test statistic to test the hypotheses.
A)3.39
B)13.125
C)0.875
D)-0.875
E)-3.39

Question

Quizplus · Accepted Answer

The test statistic is calculated using the formula: (sample mean - population mean) / (sample standard deviation / sqrt(sample size)). Here, it is (18.5 - 15) / (4 / sqrt(15)) = 3.39.

In Research on Cell Phone Use by Teenagers It Was