Question

The table on Sktterpolla show the number of hours worked, X, and the amount of money spent on entertainment, why, by each of 11 students. The equation of the line best fit is y=0.4x+22.05.Use the equation of the line of best fit to fill in the blank below. Give exact answers, not rounded approximations

Answer 1

For the values x = 9.9 and x = 12.1, we need to find the observed amount of dollars spent, the expected amount of dollars spent, and the residuals.

To find the observed amount of dollars spent, we use the table.

To find the expected amount of dollars spent, we use the line of best fit.

The residual is the difference between the observed and the expected value.

Thus, for x = 9.9:

Observed amount spent: 21.50

$Expected\text{ }amount:y=0.4\cdot9.9+22.05=26.01$$Residual:21.50-26.01=-4.51$

For x = 12.1:

Observed amount spent: 25.00

$Expected\text{ }amount:y=0.4\cdot12.1+22.05=26.89$$Residual:25-26.89=-1.89$

The answer is:

First row:

Hours: 9.9

Observed: 21.50

Expected: 26.01

Residual: -4.51

Second row:

Hours: 12.1

Observed: 25.00

Expected: 26.89

Residual: -1.89