document.write( "Question 989611: Gary has 42 coins in nickels, dimes, and quarters. If he has 8 more nickels than dimes and has $7.15 in all, how many of each does he have? \n" ); document.write( "
Algebra.Com's Answer #807877 by ikleyn(52831)![]() ![]() You can put this solution on YOUR website! . \n" ); document.write( "Gary has 42 coins in nickels, dimes, and quarters. \n" ); document.write( "If he has 8 more nickels than dimes and has $7.15 in all, how many of each does he have? \n" ); document.write( "~~~~~~~~~~~\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " It is a typical problem to be solved using one single unknown and one single equation.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " See below on how to do it . . . \r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \r\n" ); document.write( "Let x be the number of nickels;\r\n" ); document.write( "\r\n" ); document.write( "then the number od dimes is (x-8) and the number of quarters is (42 - x - (x-8)) = (42+8 - 2x) = (50-2x).\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "At this point, you can write the total money equation\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( " 5x + 10*(x-8) + 25*(50-2x) = 715 cents.\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Simplify and solve\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( " 5x + 10x - 80 + 1250 - 50x = 715\r\n" ); document.write( "\r\n" ); document.write( " -35x = 715 + 80 - 1250\r\n" ); document.write( "\r\n" ); document.write( " -35x = -455\r\n" ); document.write( "\r\n" ); document.write( " x =\r \n" ); document.write( "\n" ); document.write( "Solved.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |