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5 votes
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.

User YAKOVM
by
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2 Answers

5 votes
Using cross-multiplication:

shadow/height

2/5 = 8/x

8x5=2x
40=2x
20=x
The lamppost is 20 feet tall.
User Don Jose
by
7.9k points
3 votes
Here is a proportion

5/2 = x/8

2x = 40
/2 /2

x = 20

Hope this helps
User Ran Davidovitz
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8.3k points