SOLUTION: A researcher wanted to determine if using an octane booster would increase gasoline mileage. A random sample of seven cars was selected; the cars were driven for two weeks without
Algebra ->
Probability-and-statistics
-> SOLUTION: A researcher wanted to determine if using an octane booster would increase gasoline mileage. A random sample of seven cars was selected; the cars were driven for two weeks without
Log On
Question 729102: A researcher wanted to determine if using an octane booster would increase gasoline mileage. A random sample of seven cars was selected; the cars were driven for two weeks without the booster and two weeks with the booster. Use the definitions of X1 and X2 as given in the table. Consequently, D = X1–X2.
Gasoline Mileage
Without booster, X1
(mpg) Gasoline Mileage
With booster, X2
(mpg)
21.2 23.8
25.4 25.6
20.9 22.4
27.6 28.3
22.8 24.5
27.3 28.8
23.4 25.2
What critical value should be used at α = 0.05?
A) –2.447 B) –2.365 C) –1.943 D) –1.895
Determine the mean of the differences.
A) –1.67 B) 6.3 C) 1.67 D) –1.43
(