Question

A water tower casts a shadow that is 21 ft long. A 10 ft tall tree casts a shadow that is 8 ft long. What is the height of thewater tower?

Answer 1

Assume that the height of the tower is x

Since the shadow of x is 21 feet

Since the shadow of 10 feet is 8 feet

By using the equal ratio between the actual heights and their shadow

`(x)/(21)=(10)/(8)`

By using the cross multiplication

`\begin{gathered} x*8=10*21 \\ 8x=210 \end{gathered}`

Divide both sides by 8 to find x

`\begin{gathered} (8x)/(8)=(210)/(8) \\ x=26.25\text{ f}eet \end{gathered}`

The height of the tower is 26.25 feet