Question

Hoover Dam on the Colorado River casts a shadow that is 2,904 feet long. At the same time, an 18-foot-tall flagpole next to the dam casts a shadow that is 72 feet long. How tall is the Hoover Dam?

Answer 1

726 feet

Explanation:

Object height and shadow length are proportional, so you have ...

(object height)/(shadow length) = (18 ft)/(72 ft) = (dam height)/(2904 ft)

Then the dam height is ...

dam height = (2904 ft)(18/72) = 726 ft

Hoover Dam is 726 feet high.