Answer:
a) Option A)
[tex]H_{0}: \mu \geq 1503\\H_A: \mu < 1503[/tex]
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, [tex]\bar{x}[/tex] = $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
[tex]H_{0}: \mu \geq 1503\text{ dollars}\\H_A: \mu < 1503\text{ dollars}[/tex]
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
[tex]\text{Point estimate} = \bar{x} - \mu = 1425 - 1503 = -78[/tex]
Thus,
Point estimate of difference = -78