A 10​-ft vertical post casts a 16​-in shadow at the same time a nearby cell phone tower casts a 118​-ft shadow. How tall is the cell phone​ tower?

Answer 1

Using similar triangles, we can set up a proportion:

10 ft (height of the post) / 16 in (length of the shadow of the post) = x ft (height of the cell phone tower) / 118 ft (length of the shadow of the cell phone tower)

Cross multiplying, we get:
10 * 118 = 16x
x = 7.875 ft

Therefore, the cell phone tower is 7.875 ft tall.