Question

A car manufacturer claims that the company’s newest model has a peak power of exactly 329 horsepower. Katherine is a reporter for an automotive magazine. She is testing the manufacturer's claim and says that the population mean peak power is less than the advertised amount. She measures the peak horsepower of 42 randomly selected cars of the new model. The sample mean is 327.74 horsepower with a standard deviation of 2.41 horsepower. Should Katherine reject or fail to reject the null hypothesis given the sample data below? H0:μ=329 versus Ha:μ<329 α=0.05 (significance level) t≈−3.39 with 41 degrees of freedom p-value<0.005

Answer 1

Answer: Katherine should reject the null hypothesis.

Explanation:

We reject the null hypothesis when p-value is less than the significance level.

here, H0:μ=329 versus Ha:μ<329

α=0.05 (significance level)

p-value<0.005

so , we should reject the null hypothesis as p-value is less than the significance level.

Hence, Katherine should reject the null hypothesis.