SOLUTION: A 4 foot fountain casts a 15 foot shadow, while the flagpole casts a 180 foot shadow. How tall is teh flagpole?

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Question 151263: A 4 foot fountain casts a 15 foot shadow, while the flagpole casts a 180 foot shadow. How tall is teh flagpole?
Found 2 solutions by HyperBrain, Earlsdon:
Answer by HyperBrain(694) About Me  (Show Source):
You can put this solution on YOUR website!
The ratio that we will use is original length:shadow length
We will apply ratio and proportion:
4%2F15=x%2F180
By cross multiplication,
4(180)=15x
15x=4(180)
15x=720
5x=240
x=48

Therefore, the the flagpole is 48 ft tall.

Power up,
HyperBrain!

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
You can use similar right triangles for this problem.
In similar triangles, corresponding sides are proportional.
The first right triangle is formed by the height of the fountain (4') and its shadow (15').
The second right triangle is formed by the height of the flag pole (h) and its shadow (180').
So, from this you can write the proportion:
4%2F15+=+h%2F180 Solve this for h, the height of the flag pole.
4%28180%2F15%29+=+h
h+=+48feet.