A large automobile manufacturing company is trying to decide whether to purchase brand A or brand B tires for its new models. To help arrive at a decision, an experiment is conducted using 12 of each brand. The tires are run until they wear out. The results are: Sample Mean Sample Standard Deviation Brand A 37 900 kilometers 5 100 kilometers Brand B 39 800 kilometers 5 900 kilometers Test the hypothesis that there is no difference in the average wear of 2 brands of tires. Use a = 0.01. Assume the populations to be normally distributed with unknown and equal variances. Present all five steps for a HTP.

Question 12(...../ 10 points) A large automobile manufacturing company is trying to decide whether to purchase brand A or brand B tires for its new models. To help arrive at a decision, an experiment is conducted using 12 of each brand. The tires are run until they wear out. The results are: Sample Mean Sample Standard Deviation Brand A 37 900 kilometers 5 100 kilometers Brand B 39 800 kilometers 5 900 kilometers Test the hypothesis that there is no difference in the average wear of 2 brands of tires. Use o =0.01. Assume the populations to be normally distributed with unknown and equal variances. Present all five steps for a HTP. Solution