Answer:
a) Option A)
b) Point estimate of difference = -78
Step-by-step explanation:
We are given the following in the question:
Population mean, μ = $1,503
Sample mean, = $1,425
Sample size, n = 25
Sample standard deviation, s = $160
We have to carry a hypothesis test that the mean annual premium in Pennsylvania is lower than the national mean annual premium.
a) First, we design the null and the alternate hypothesis
b) Point estimate of the difference between the mean annual premium in Pennsylvania and the national mean
Point estimate of difference =
Mean annual premium in Pennsylvania - National mean
Thus,
Point estimate of difference = -78