document.write( "Question 815179: a person has 175 coins and he wants to arrange the coins in some rows and columns such that the number of columns is twice the number of rows .what is the minimum number of additional coins needed for such an arrangement \n" ); document.write( "
Algebra.Com's Answer #490753 by Edwin McCravy(20065)\"\" \"About 
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document.write( "Let the number of rows be x\r\n" );
document.write( "Then the number of columns will be 2x\r\n" );
document.write( "Then the number of coins will be (x)(2x)\r\n" );
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document.write( "Then (x)(2x) ≧ 175\r\n" );
document.write( "         2x² ≧ 175\r\n" );
document.write( "Divide both sides by 2:\r\n" );
document.write( "          x² ≧ 87.5\r\n" );
document.write( "Take positive square roots of both sides:\r\n" );
document.write( "           x ≧ √87.5\r\n" );
document.write( "           x ≧ 9.354143467S\r\n" );
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document.write( "So the smallest whole number x can be is 10\r\n" );
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document.write( "So there would be 10 rows and 20 columns.\r\n" );
document.write( "That would be 10×20=200 coins.\r\n" );
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document.write( "So we'd need 200-175 or 25 more coins.  \r\n" );
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document.write( "Edwin
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