Area of a Rectangle Outside a Rectangle
Date: 6/11/96 at 2:20:13 From: Anonymous Subject: Area of a rectangle not in another rectangle A rectangular swimming pool 50 m by 32 m has a concrete border all around it. Find the area of the concrete border if it is 2.4 m wide at the sides and 4.8 m wide at the ends. The concrete path is to be tiled with square tiles of side 20 cm each. How many tiles will be needed? A big group of Singaporean friends and I have been stumped over this question. We sincerely hope that you can help us. There seem to be many different ways to do this question and the answers range widely. Yours sincerely, Jeannette signin' off from Sunny Singapore
Date: 6/12/96 at 13:46:52 From: Doctor Darren Subject: Re: Area of a rectangle not in another rectangle I would approach this problem by finding the area of the rectangle you want _including_ the path and the pool (which has length 50+2*4.8 = 59.6 m, and width 32+2*2.4 = 36.8 m) so the area is 2193.28 m^2. We then subtract the area of the pool, which is 1600 m^2, and the area of the concrete border is 593.28 m^2. Does this agree with any of your answers? -Doctor Darren, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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