SOLUTION: A flagpole 20 feet high casts a shadow of 5 feet. At the same time, a nearby building casts a 20-foot shadow. How many feet high is the building? (Note: The ground is level and bot

Algebra ->  Customizable Word Problem Solvers  -> Misc -> SOLUTION: A flagpole 20 feet high casts a shadow of 5 feet. At the same time, a nearby building casts a 20-foot shadow. How many feet high is the building? (Note: The ground is level and bot      Log On

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Question 19763: A flagpole 20 feet high casts a shadow of 5 feet. At the same time, a nearby building casts a 20-foot shadow. How many feet high is the building? (Note: The ground is level and both the building and the flagpole are perpendicular to the ground.)











































Answer by mmm4444bot(95) About Me  (Show Source):
You can put this solution on YOUR website!
Hello There:
This is a problem that can be solved using similar triangles. Both the flagpole and its shadow and the building and its shadow are legs of right triangles. Their sides are proportional.
Let h = the height of the building.
Then we can say that h is to 20 feet as 20 feet is to 5 feet.
h/20 = 20/5
h/20 = 4
h = 80
The building is 80 feet high.
~ Mark