A car company claims that their Super Spiffy Sedan averages 31 mpg. You randomly select 8...

A car company claims that their Super Spiffy Sedan averages 31 mpg. You randomly select 8 Super Spiffies from local car dealerships and test their gas mileage under similar conditions.

You get the following MPG scores:

MPG:

30,

28,

32,

26,

33,

25,

28,

We wan to test whether the actual gas mileage for these cars deviate significantly from 31 (alpha = .05).

1- Are we given the value of the population mean (μ)?

2- What is the the standard error?

3- What is the the null hypothesis?

4- What is the the value of the test statistic?

5- Based on the p-value you obtained, should we reject the null hypothesis at significance level α = 0.05?

6- What is a 95% confidence interval for the mean actual gas mileage of the company's cars?

Solutions

Expert Solution

orchestra answered 1 year ago

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