SOLUTION: A circular pool is 46 feet in diameter and has a flag stone walk around it that is 4 feet wide. Find the area of the walk. Express the answer in terms of {{{pi}}}.
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Question 169634: A circular pool is 46 feet in diameter and has a flag stone walk around it that is 4 feet wide. Find the area of the walk. Express the answer in terms of . Found 2 solutions by Alan3354, Edwin McCravy:Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! A circular pool is 46 feet in diameter and has a flag stone walk around it that is 4 feet wide. Find the area of the walk. Express the answer in terms of pie.
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Adding 4 ft to both sides gives an outside diameter of the walk of 54 ft.
The area of the walk is the area of a 54 ft dia circle minus the area of the pool.
Using the radii is simpler, they're 27 ft and 23 ft. So it's
pi*27^2 - pi*23^2
= 729pi - 529pi
= 200*pi sq ft.
BTW, it's pi, the Greek letter, not pie.
A circular pool is 46 feet in diameter and has a flag stone walk around it that is 4 feet wide. Find the area of the walk. Express the answer in terms of .
Here is the pool only, which is 46 feet across.
So it has a radius of half that, or 23 feet:
The area of the pool is given by the formula
It has a walk around it which is 4 feet wide.
If we take out the inner circle, like this:
we see that the outer circle, which includes both the
pool and the walk, has a radius of
or feet.
The area of the outer circle which includes
the pool and the walk is given by the formula:
Going back to the original picture:
AREA OF WALK = AREA OF OUTER CIRCLE - AREA OF INNER CIRCLE =
square feet.
Edwin
