document.write( "Question 1207439: 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 thepool.If the border is to have a depth of 3 inches,how wide will the border be? (1 cubic yard 27 cubic feet).\r
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Algebra.Com's Answer #845306 by MathTherapy(10552)\"\" \"About 
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document.write( "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 thepool.If the border is to have a depth of 3 inches,how wide will the border be? (1 cubic yard 27 cubic feet).\r\n" );
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document.write( "I need the set up here. \r\n" );
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document.write( "Thanks. \r\n" );
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document.write( "Since radius of smaller circle (pool) is 5' (\"10%2F2\"), the radius of the larger circle (pool + border) = 5 + w\r\n" );
document.write( "Area of smaller circle (pool) = πr2 = 25π\r\n" );
document.write( "Area of larger circle (pool + border) = πr2 = π(5 + w)2 = π(25 + 10w + w2)\r\n" );
document.write( "Area of border = π(25 + 10w + w2) - 25π = 25π + 10πw + πw2 - 25π = 10πw + πw2\r\n" );
document.write( "Since height of border = 3”, or \"matrix%281%2C4%2C+3%2F12%2C+%22=%22%2C+1%2F4%2C+foot%29\", volume of border = (π10w + πw2)\"1%2F4\" = \"%2810%2Api%2Aw+%2B+pi%2Aw%5E2%29%2F4\"\r\n" );
document.write( "As volume of border = 1 cubic yard, or 27 cubic feet, we then get: \"matrix%281%2C3%2C+%2810%2Api%2Aw+%2B+pi%2Aw%5E2%29%2F4%2C+%22=%22%2C+27%29\"\r\n" );
document.write( "                              10πw + πw2 = 108 ---- Cross-multiplying\r\n" );
document.write( "                        πw2 + 10πw - 108 = 0\r\n" );
document.write( "Using the quadratic equation formula: \"matrix%281%2C3%2C+w%2C+%22=%22%2C+%28-+b+%2B-+sqrt%28b%5E2+-++4ac%29%29%2F%282a%29%29\", with: a = π\r\n" );
document.write( "                                                                    b = 10π\r\n" );
document.write( "                                                                    c = - 108\r\n" );
document.write( " \"matrix%281%2C3%2C+w%2C+%22=%22%2C+%28-+b+%2B-+sqrt%28b%5E2+-++4ac%29%29%2F%282a%29%29\" then becomes: \r\n" );
document.write( "     Width of border, or     OR
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