1.  An investigator wishes to compare the average timeto relief of headache pain under three
distinct medications, call them Drugs A, B, and C. Fifteenpatients who suffer from chronic
headaches are randomly selected for the investigation, and fivesubjects are randomly assigned
to each treatment. The following data reflect times to relief(in minutes) after taking the
assigned drug.
Test if there is a significant difference in the mean timesamong three treatments. Use α =
0.05. (apply ANOVA)
| Drug A | Drug B | Drug C |
| 30 | 25 | 15 |
| 35 | 21 | 20 |
| 40 | 30 | 25 |
| 25 | 25 | 22 |
| 35 | 30 | 24 |
a) State the null and alternative hypothesis.
Null: all means are equal
Alternative: Atleast one mean is different
b) State your conclusion about the hypothesis based on the teststatistic and critical value
Reject the hypothesis because there is a huge difference betweenthe 3 treatments and their means
c) Perform multiple comparison test to show whetherthere are significant differences between the drugs
