A consumer organization examined the relationship between the weight of a car (in thousands of pounds) and the fuel efficiency (in miles per gallon or mpg). Part of the regression is shown below, where the response variable is fuel efficiency.
Dependent variable is fuel efficiency
R squared = 78.3 %
s=2.882 with 50-2 = 48 degrees of freedom
variable Coeff SE (Coeff)
intercept 47.32 2.26
weight -8.49 0.58
mean weight = 2811 pounds
Find :
A) Create aa 99% confidence interval for the average fuel efficiency among car weighing 2500 pounds.
B) Create a 99% prediction interval for the gas mileage you might get driving your new 3450-pound SUV.