Question

You work for a consumer advocacy agency and want to estimate the populations means cost of monthly maintenance on a car. It is assumed that the average monthly cost of maintenance is $210 dollars. In a random sample of 100 cars, you find the average monthly maintenance cost was $185. Assume that the population standard deviation is known to be $125; Use a 0.03 significance level to test the claim that the population mean weight of cost of maintenance differs from 210 lbs. State the null and alternate hypothesis test
A) H0: μ≤185
Ha: μ>185

B) H0: μ≥210
Ha: μ<210

C) H0=210
Ha: μ=185

D) H0: μ=210
Ha: μ ≠ 210

Answer 1

According to the desired test, the hypothesis are given by:

D) H0: μ=210

Ha: μ ≠ 210

At the null hypothesis, it is tested if the population mean is of 210 lbs, that is:

$H_0: \mu = 210$

At the alternative hypothesis, it is tested if the population mean differs from 210 lbs, that is:

$H_a: \mu \neq 210$

Hence, the correct option is:

D) H0: μ=210

Ha: μ ≠ 210

A similar problem is given at brainly.com/question/25707631