2. A sport trainer wants to know whether the true average time of his athlete who do 100-meter sprint is 98 seconds. He recorded 18 trials of his team and found that the average time is 98.2 seconds with a standard deviation of 0.4 second. Is there sufficient evidence to reject the null hypothesis if μ = 98 seconds at the 0.05 level of significance?
A. Test statistic t = 2.1213 is a value greater than the critical value to = + 2.110. Hence, the test value is clearly in the critical region. Thus, we decide to reject the null hypothesis.
B. Test statistic t = -2.1213 is a value lesser than the critical value to = + 2.110. Hence, the test value is clearly outside the critical region. Thus, we decide to reject the null hypothesis.
C. Test statistic t = 2.1213 is a value greater than the critical value to = + 2.110. Hence, the test value is clearly in the critical region. Thus, we decide to accept the null hypothesis.
D. Test statistic t = - 2.1213 is a value lesser than the critical value to = +2.110. Hence, the test value is clearly outside the critical region. Thus, we decide to accept the null hypothesis.
Solution:
