Question

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

Answer 1

The answer you are looking for is 42. 

Answer 2

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.