Question

Three different brands of tires were compared for wear characteristics. From each brand of tire, six (6) tires were randomly selected and subjected to standard wear-testing procedures. The average mileage obtained for each brand of tire and sample variances (both in 1,000 miles) are shown below.

	Brand A	Brand B	Brand C
Average Mileage	37	38	33
Sample variance	3	4	2

            At 95% confidence, using both critical value and P-value to test to see if there is a significant difference in the average mileage of the three brands.

Answer 1

Answer:-

Given that:-

Brand A Brand B Brand C

Average Mileage 37 38 33

Sample variance 3 4 2

for Brand A

t - test

  

So, we reject null hypothesis of no significance

p- value for t = 52.85 would be at

i.e   reject

for Brand B

stat

  reject null hypothesis of no significance

for t=46.56 p - value would be at

reject

for Brand c

   reject null hypothesis of no significance

p-value would be at

reject