Two boats the prada (Italy) and the oracle (USA) are competing for a spot in the upcoming Americans cup race. They race over a part of the course several times. Below are the sample times in minutes at the .05 significance level. Can we conclude that there is a difference in their mean times?
12.9, 12.5, 11.0, 13.3, 11.2, 11.4, 11.6, 12.3, 4.2, 11.3
14.1, 14.1, 14.2, 17.4, 15.8, 16.7, 16.1, 13.3, 13.4, 13.6
18. The management of White Industries is considering a new method of assembling its golf cart. The present method requires 42.3 minutes, on the average, to assemble a cart. The mean assembly time for a random sample of 24 carts, using the new method, was 40.6 minutes, and the standard deviation of the sample was 2.7 minutes. Using the .10 level of significance, can we conclude that the assembly time using the new method is faster?
Solution. Denote by the mean assembly time. So,
Use t-test. The test statistic can be calculated as follows.
So, we should reject the null hypothesis H0. ...
This solution contains a detailed explanation of testing the difference of the means of two populations