Question

A high school counselor wants to look at the relationship between GPA and the numberof absences for students in the senior class this year. That data shows a linear patternwith the summary statistics shown below.I answered som of it I just can’t do part D, part E, part F

Answer 1

D.

The slope of a line means the increase in y for each unitary increase in x:

`b=(\Delta y)/(\Delta x)`

If the slope is equal to -0.1625, that means if x increases 1 unit, y will decrease by 0.1625 units.

E.

Using x = 3 in the regression equation, we have:

`\begin{gathered} y=a+bx \\ y=3.71-0.16x \\ y=3.71-0.16\cdot3 \\ y=3.71-0.48 \\ y=3.23 \end{gathered}`

So the estimated GPA is 3.23.

F.

If r is the value of the standard deviation, therefore r² is the variance:

`\begin{gathered} r=-0.65 \\ r^2=0.4225 \end{gathered}`

The variance is the average of the squared difference from each point to the mean, and it measures the average of how much each point differs from the mean.