Answer:
It is not evident the mean annual premium in Pennsylvania is lower than the national mean annual premium
Step-by-step explanation:
Given that annual premium for automobile insurance in the United States (Insure website, March 6, 2014), are as follows:
Mean 1440.00
SD 165.00
SEM 33.00
N 25
a) [tex]H_0: \bar x = 1503\\H_a: \bar x <1503[/tex]
(left tailed test at 5% level)
b) a point estimate of the difference between the mean annual premium in Pennsylvania and the national mean
=[tex]1440-1503\\=-103[/tex]
c) df = 24
standard error of difference = 33.000
t = 1.9091
The 95% confidence interval of this difference:
From -131.11 to 5.11
p value = 0.0683
Since p >0.05, we accept H0
It is not evident the mean annual premium in Pennsylvania is lower than the national mean annual premium