Question

Identify the null hypothesis, alternative hypothesis, test statistic, P-value, conclusion about the null hypothesis, and final conclusion that addresses the original claim. Test the claim that the mean lifetime of car engines of a particular type is greater than 220,000 miles. Sample data are summarized as n = 23, ?̅ = 226,450 miles, and s = 11,500 miles. Use a significance level of ? = 0.01.

Answer 1

Solution :

= 220000

=226450

S =11500

n = 23

This is the right tailed test .

The null and alternative hypothesis is ,

H0 :    = 220000

Ha : > 220000

Test statistic = t

= ( - ) / S / n

= (226,450-220000 ) / 11500 / 23

= 2.69

Test statistic = t = 2.69

P-value =0.0067

= 0.01

P-value <

0.0067 < 0.01

Reject the null hypothesis .

There is sufficient evidence to suggest that