A study investigated if cell phone use impacted student drivers' reaction times. There were two groups: 29 students were assigned to the cell phone group while 29 students were assigned to the control group. The experiment measured the response time to traffic lights; for the cell phone group, the mean was 588.1 with a standard deviation of 87.1 and for the control group, the mean was 531.3 with a standard deviation of 68.2. Construct a 90% confidence interval for the difference in mean response times between the cell phone and control groups.

Point Estimate:

x bar

p hat

x bar 1 - x bar 2

p1 - p2

=

Margin of Error: E =(round to 4 decimal places)

Lower Limit:(round to 4 decimal places)

Upper Limit:(round to 4 decimal places)

We are% confident that the true

population mean

population proportion

difference in population means

difference in population proportions

is betweenand.