A scale model of a building is 2.3 feet high. The ratio of the height of the model to the height of the building is 1:156. How tall is the building, in feet?

Question

anonymous · Answer

so 1 ft (model) = 156 ft (real)
therefore 2.3 ft (model) = 156 * 2.3 (real)

mathstudent55 · Answer

A scale is a ratio.
Set that ratio equal to a ratio containing the unknown height of the building and the height of the model.
Two ratios that are equal are a proportion.
Then solve the proportion.

model            1                2.3 ft
                   ----  =    --------
real               156              x

Cross multiply to solve for x