a model house is 12 inches wide. If it is built with a scale of 3 in : 20 ft, then how wide is the real house?

Answer 1

This can be solved using a proportion

Let x= the width of the real house

3 in/20 ft = 12 in/x Cross multiply to solve

3(x) = 20(12) Simplify

3x=240 Divide both sides by 3

3x/3=240/3 Simplify

x=80 ft

Answer 2

Hi Mari,

12 inches = 1 foot, and 3 inches = .25 foot.

Use the proportion

.25 ft/20 ft = 1 ft/x ft

Cross multiply to get

.25x = 20(1)

x = 80 ft.

Regards,

Anita A.