Question

Shayla is 5 feet tall and casts a shadow 2 feet long. at the same time, a nearby lamppost casts a shadow 8 feet long. write and solve a proportion to find the height of the lamppost.

Answer 1

Using cross-multiplication:

shadow/height

2/5 = 8/x

8x5=2x
40=2x
20=x
The lamppost is 20 feet tall.

Answer 2

Here is a proportion

5/2 = x/8

2x = 40
/2      /2

x = 20

Hope this helps