Question

Problem. A building casts a shadow that is 30 feet long. At the same time a flagpole that is 15 feet tall casts a shadow 10 feet long. How tall is the building?

Answer 1

EXPLANATION

Let's see the facts:

Shadow = 30 feet long

height of the building = unknown

flagpole height = 15 feet

flagpole shadow = 10 feet

We can set up a proportion comparing the height of each object to the length of the shadow.

`(h)/(s)`
`(h)/(30)=(15)/(10)`

Multiplying both sides by 15:

`h=30\cdot(15)/(10)`

Multiplying numbers:

`h=(450)/(10)=45_{\text{ }}\text{feet}`

The height is 45 feet