The Great Plains Railroad is interested in studying how fuel

The Great Plains Railroad is interested in studying how fuel consumption is related to the number of railcars for its train on a certain route between Oklahoma City and Omaha. A random sample of 10 trains on this route has yielded the data in the table below. number of railers fuel consumption (x-value y-value) 20 58 // 20 52 // 37 91// 31 80 // 47 114 // 43 98 // 39 87 // 50 122 // 40 100 // 29 70

A (3pts) State the sum of square errors.

B (5 pts) State the standard error of the slope and interpret that value.

C (6pts) Calculate the 95% confidence interval for slope.

D (7pts) From the coefficient of determination, standard error of slope, and the confidence interval for slope does that model appear to fit well? Explain.

E (5pts) Use your model (if it fits well – see answer in part k) to predict the fuel consumption for a train with 47 railcars.

F (4 pts) What is the residual value for the fuel consumption for a train with 47 railcars?

G (5 pts) Why would it not be reasonable to use the fitted regression equation to predict the fuel consumption for a train on this route if the train had 75 railcars?

Solution