document.write( "Question 1048464: A circular pool measures 10 feet across. One cubic yard of concrete is to be used to create a circular border of uniform width around the pool. If the border is to have a depth of 3 inches, how wide will the border be? Use 3.14 to approximate π. Express your solution rounded to two decimal places. (1 cubic yard = 27 cubic feet).
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Algebra.Com's Answer #664066 by ankor@dixie-net.com(22740)\"\" \"About 
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A circular pool measures 10 feet across. One cubic yard of concrete is to be used to create a circular border of uniform width around the pool.
\n" ); document.write( " If the border is to have a depth of 3 inches, how wide will the border be?
\n" ); document.write( " Use 3.14 to approximate π. Express your solution rounded to two decimal places. (1 cubic yard = 27 cubic feet).
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\n" ); document.write( "let w = the width of the border
\n" ); document.write( "3 inches = .25 ft
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\n" ); document.write( "Then the circular area including pool and the border, radius =(w+5)
\n" ); document.write( "Border area = Total area - pool area
\n" ); document.write( "B.A = \"pi%2A%28w%2B5%29%5E2+-+pi%2A5%5E2\"
\n" ); document.write( "B.A = 3.14(w^2 +10w + 25) - (3.14*25)
\n" ); document.write( "B.A.= 3.14w^2 + 31.4w + 25 - 78.5
\n" ); document.write( "B.A.= 3.14w^2 + 31.4w - 53.5
\n" ); document.write( "Using the volume (27) given and thickness of this area (.25ft)
\n" ); document.write( ".25(3.14w^2 + 31.4w - 53.5) = 27
\n" ); document.write( ".785w^2 + 7.85w - 13.375 - 27 = 0
\n" ); document.write( "a quadratic equation
\n" ); document.write( ".785w^2 + 7.85w - 13.625 = 0
\n" ); document.write( "I got a positive solution
\n" ); document.write( "w = 1.51 ft wide, the concrete border\r
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