Data for total power costs and machine hours are given below.
|
Power Costs
|
Machine Hours
|
|
(000 omitted)
|
(000 omitted)
|
|
$ 7
|
9 hours
|
|
6
|
8
|
|
8
|
8
|
|
3
|
4
|
|
4
|
6
|
|
8
|
7
|
|
8
|
9
|
|
6
|
5
|
|
7
|
8
|
|
5
|
6
|
|
$62
|
70 hours
|
1. Separate the power costs into the fixed and variable components using the method of least squares. Estimate the power costs when 6.5 machine hours are used.
2. Compute the coefficient of determination.
3. Does the regression equation need to be improved?