Acar company claims that its cars achieve an average gas mileage of at least 26 miles per gallon. a random sample of five cars form this company have an average gas mileage of 25.2 miles per gallon and a standard deviation of 1 mile per gallon. at α=0.06, can the company’s claim be supported, assuming this is a normally distributed data set?

Let be the population mean.

Null hypothesis :

Alternative hypothesis :

Since the alternative hypothesis is left tailed, so the test is a left-tailed test.

Sample size : n=5 <30 , so we use t-test.

Test statistic:

Critical t-value for t=

Since, the absolute value of t (1.79) is less than the critical t-value , so we fail to reject the null hypothesis.

Hence, we have sufficient evidence to support the company's claim.

1/8 miles

Step-by-step explanation:

You have to subtract  for the answer.

First, you gotta make 3/4 have a common denominator.

To do this multiply 3/4 by 2/2 (2/2 equals one, so value isn't changed.)

and you get 6/8.

Then you can subtract 6/8 - 5/8 to get 1/8 miles.

And there's no need to simplify 1/8.