Question

Using the data below, what is the equation for the line of best fit? Remember, put your answer in y = ax + b form and round any decimals to three places.
Patient Calories Wt. loss/week lbs.
1 1500 2
2 1200 3
3 1800 1
4 2100 .5
5 2400 .75
6 1800 1
7 1200 5
8 2100 1
9 2400 .5
10 1500 2

Answer 1

If we fit the data as calories as a function of wt loss/week, we need to arrange the data first from lowest to highest wt loss/week lbs and calories. Then, the set of points can be plotted in a graph and a graphical method of line fitting can be used. Curve fitting programs (which are also in the calculator) can be used. The result is:
y = -266.5741x + 2246.5116

The value of R² is 0.7109. The fit is not very good since R² is quite far from 0.99.