Question: Bjork Larsen was trying to decide whether to use racing wax for cross-country skis. He decided that the was would be worth the price if he could average less than 55 seconds on course he knew well, so he planned to test the was by racing on the course 8 times.

a) Suppose that he eventually decides not to buy the wax, but it really would lower his average time to below 55 seconds. What kind of error would he have made?

b) His 8 race times were: 56.3, 65.9, 50.5, 52.4, 46.5, 57.8, 52.2 and 43.2 seconds. Should he buy the wax? Explain.