Based on the scatterplot below, what is the most likely value for “Pounds of Apples” when “Number of Apples” is 80?

Find the approx. slope of the regression line through the given 5 points.  As x increases from 9 to 45 (a change of +36), y increases from 5 to 25, or 20.
                                                                                     20         5
Thus, the slope of the regression line is approx. m = ------ = -----
                                                                                     36         9
We need to continue, to find the equation of this regression line.

Since the slope is 5/9 and one point on the line is (25,12), the equation of the line is:

y-12 = (5/9)(x-25).

Now let x = 80 and calculate y:      y = 12 + (5/9)(55) = 12 = 42.6

When the # of apples is 80, the weight of the apples is approx. 43 lb.