A biology student wanted to test whether taking ginseng supplementswould result
ID: 2955161 • Letter: A
Question
A biology student wanted to test whether taking ginseng supplementswould result in improved athletic performance. He randomly selected20 students to participate in his study. Each student was tested ona treadmill at maximal effort for 15 minutes. The number ofcalories burned (as reported by the treadmill’s display) wasused as a measure of how much work each student was capable ofperforming in that time. The students were then given supplementsto take daily for 8 weeks. They were then tested on the treadmillagain. The data obtained are presented below:Before supplements: ni = 20 i = 160.9 and si = 42.02
After supplements: nf = 20 f = 165.2 and sf = 51.18
Difference: nd = 20 = 4.3 and sd = 22.47
a) State the null hypothesis and the alternative hypothesis. Makesure you clearly indicate which parameter is for the initial dataand which is for the final data.
Ho:
Ha:
b) Calculate the test statistic. Specify which test statistic youare finding (“z” or “t”).
c) Find the p-value using the appropriate table. Draw the curve andhighlight the corresponding area.
d) At a significance level of 0.05, would you reject or retain thenull hypothesis. Circle your response and explain why you chosethis response, using the p-value you found in part c.
Reject Ho / Do NOT Reject Ho Why?
e) Interpret the result. Make sure to include the weight of theevidence, the conclusion, and the significance level