In a statistics class, students took their pulses before and after being frightened. The frightening event was having the teacher scream and run from one side of the room to the other. The pulse rates (beats per minute) of the women before and after the scream were obtained separately and are shown in the accompanying table. Treat this as though it were a random sample of female community college students. Test the hypothesis that the mean of college women's pulse rates is higher after fright, using a significance level of 0.05.
Pulse before: 65, 77, 95, 92, 94, 71, 70, 82, 81, 61, 82, 89, 64
Pulse after: 67, 85, 96, 99, 97, 77, 78, 86, 84, 65, 87, 95, 74
Step 1: Hypothesize
Let μ_before be the population mean number of beats per minute before the scream, and let μ_after be the population mean number of beats per minute after the scream. Determine the hypotheses for this test. Choose the correct answer below.
Choose a test. Should it be a paired t-test or a two-sample t-test? Why?
Step 3: Compute to compare
Find the test statistic for this test. Use μ_difference = μ_before minus μ_after.
t = (Round to two decimal places as needed.)
Find the p-value for this test.
p-value = (Round to three decimal places as needed.)
Step 4: Interpret
Reject or do not reject H0.
Then write a sentence that includes "significant" or "significantly" in it. Report the sample mean pulse rate before the scream and the sample mean pulse rate after the scream.