A circular swimming pool has diameter 40 feet and is centered in a fenced-in square region measuring 70 feet by 70 feet. A concrete sidewalk 5 feet wide encircles the pool, and the rest of the region is grass, as shown in the figure below. (Round your answers to one decimal place.)
find the area of the concrete strip
Geometry question about a swimming pool?
2012-06-27 12:15 am
回答 (4)
2012-06-27 12:21 am
✔ 最佳答案
Side walk area = pi(25^2-20^2) =225pi ft^2
2016-11-30 8:10 am
area of pool = 20 x 35 = seven-hundred feet^2 Perimeter of backyard = 2 * (L + W) = 360 = 2 * (L + 70) 360/2 = 2/2 * (L + 70) a hundred and eighty = L + 70 L + one hundred ten feet area of backyard = one hundred ten * 70 = 7700 feet^2 area minus pool = 7700 - seven-hundred = 7000 feet^2
2012-06-27 12:23 am
Look at the picture.
Area(concrete) = Area(whole circular region) - Area(pool)
diameter of whole region is 50[r = 25] and diameter of pool is 40[r = 20]
A(c) = 625π - 400π = 225π ft² = 706.9 ft²
Area(concrete) = Area(whole circular region) - Area(pool)
diameter of whole region is 50[r = 25] and diameter of pool is 40[r = 20]
A(c) = 625π - 400π = 225π ft² = 706.9 ft²
2012-06-27 12:19 am
radius of the circle including concrete strip is 25 radius of the pool is 20
area of concrete strip = pi(25)^2-pi(20)^2=pi(625-400)=225pi
area of concrete strip = pi(25)^2-pi(20)^2=pi(625-400)=225pi
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