The height of a person in a scale drawing is 4 inches. The person's actual height is 64 inches. What is the scale factor that is used to make the drawing?

Answer 1

Let X be the scale factor. Then simply make a proportion:

4 is to 64 as 1 is to X: 4/64 = 1/X. Solving for X by cross multiplying, we have

4/64 x 1/X, 1 x 64 = 4X, X = 64/4 = 16. A fast check: to find the actual height of a person 4 inches in the drawing, multiply by the scale factor 16;

4 (in drawing) x 16 = 64 inches (actual).

Answer 2

The scale factor is what you multiply all of the "real" measurements by in order to get the drawing measurements. So we need to ask ourselves: "Real * what = drawing" ? Re-written,

64x = 4, so

x = 1/16