<PRE><B>Question 1057369</B>
A circular swimming pool has diameter 50 feet and is centered in a fenced-in square region measuring 80 feet by 80 feet. A concrete sidewalk 5 feet wide encircles the pool, and the rest of the region is grass, as shown in the figure below. (I added a link to the picture used in the problem. https://www.dropbox.com/s/jxc7syj05xb0lrh/8-1-023.gif?dl=0 )

Find the surface area of the water
-- Area = pi*r^2 = pi*25^2 = 625pi sq feet.
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Find the area of the concrete sidewalk
r to the outside of the concrete = 25+5 = 30 feet
Area = pi*30^2 - area of the water
= 900pi - 625pi sq feet = 225pi sq feet
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Find the area of the grass
= 80*80 - the other 2 areas
= 6400 - 900pi sq ft.
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