Question

1. A tire manufacturer claims that their all weather tires stop faster than a competitor’s. In order to test this claim, a consumer advocacy group records the stopping distance in feet of 9 different cars traveling at 60 miles per hour, once outfitted with the manufacturer’s tires and once with the competitor’s tires. The stopping distances are recorded below:

   Car	1	2	3	4	5	6	7	8	9
   Manufacture tires	92.4	98.9	101.3	94.6	110.2	89.4	120.5	90.6	86.4
   competitors tires	94.5	99.2	102.1	95.3	109.1	92.3	118.3	91.2	86.5

   Assume that the conditions for inference have been met. Does this information provide evidence that the manufacturer’s tires have a shorter stopping distance? Use ? = 0.1

Answer 1