Question 1010299
Ho=Takes 13.5 or more minutes.
Ha=takes <13.5 minutes
alpha =0.10
one way t-test with df=7
critical value is t <-1.415
t=(xbar-13.5)/s/sqrt(n)
=12.7625-13.5/(1.2454)/sqrt(7)
t=-1.67; p=0.07
95% CI is (11.72,13.80)
Note that with higher confidence, the critical point of 13.5 is within the confidence interval. This is consistent with a p-value between 0.05-0.10.