document.write( "Question 1181645: The ball of a float valve has a diameter of 4 in., and the thickness of the metal is 0.05 in. How much does it weigh if it is made of copper? (Copper weighs 556 lb. per cu. ft.) \n" ); document.write( "

Algebra.Com's Answer #811650 by ikleyn(52786) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "            The solution by @mananth is FATALLY INCORRECT !\r
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\n" ); document.write( "\n" ); document.write( "            It contains a FATALL ERROR !\r
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\n" ); document.write( "\n" ); document.write( "            If to combine all incorrect solutions/answers by @mananth at this forum,
\n" ); document.write( "            it would comprise an entire book showing all possible and typical errors
\n" ); document.write( "            and teaching on how Math problems should not be solved at any circumstances !\r
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\n" ); document.write( "\n" ); document.write( "            See my correct solution below.\r
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document.write( "Outer volume - inner volume = volume of copper.\r\n" );
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document.write( "Volume of copper * density of copper = weight of copper\r\n" );
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document.write( "outer radius = R = 2 inches\r\n" );
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document.write( "inner radius = r = 2- 0.05 = 1.95 inches.\r\n" );
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document.write( "Volume of copper =  -  = \r\n" );
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document.write( "V= 2.449 in^3\r\n" );
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document.write( "556 lb/ft^3 = 0.322 lb/in^3\r\n" );
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document.write( "Weight of copper = 2.449 * 0.322 = 0.789 pounds.     ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( " Notice that the correct answer is about 5000 times the incorrect answer by @mananth ( ! ) ( ! ! ) ( ! ! ! )\r
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