Answer:
Step-by-step explanation:
Given that the sample mean for a random sample of 100 cars is 27.2 miles and assume the standard deviation is 2.4 miles.
H0: x bar = 25.9
Ha: x bar ≠25.9
(Two tailed test at 95% confidence)
Alpha =0.05
The hypothetical mean is 25.900 Â
The actual mean is 27.200 Â
The difference between these two values is 1.300 Â
The  95% confidence interval of this difference: Â
From -3.462 to 6.062
t = 0.5417 Â
 df = 99 Â
 standard error of difference = 2.400
The two-tailed P value equals 0.5893 Â
 Since p >0.05 this difference is considered to be not statistically significant. Â