document.write( "Question 1052972: Harry has $6.10 in his pocket. He has twice as many quarters as nickels and one more dime than quarters. How many of each coin does Harry have \n" ); document.write( "
Algebra.Com's Answer #668272 by Edwin McCravy(20056)![]() ![]() You can put this solution on YOUR website! Harry has $6.10 in his pocket. \n" ); document.write( " \r\n" ); document.write( "$0.25Q + $0.10D + $0.05N = $6.10\r\n" ); document.write( "\r\n" ); document.write( "or multiplying through by 100,\r\n" ); document.write( "\r\n" ); document.write( "25Q + 10D + 5N = 610\r\n" ); document.write( "\r\n" ); document.write( "dividing through by 5\r\n" ); document.write( "\r\n" ); document.write( "5Q + 2D + N = 122\r\n" ); document.write( " \n" ); document.write( "He has twice as many quarters as nickels \n" ); document.write( " \r\n" ); document.write( "Q = 2N\r\n" ); document.write( " \n" ); document.write( " and \r \n" ); document.write( "\n" ); document.write( "one more dime than quarters. \n" ); document.write( " \r\n" ); document.write( "D = Q + 1\r\n" ); document.write( "\r\n" ); document.write( "So we have this system of equations:\r\n" ); document.write( "\r\n" ); document.write( "1. 5Q + 2D + N = 122\r\n" ); document.write( "2. Q = 2N\r\n" ); document.write( "3. D = Q + 1\r\n" ); document.write( "\r\n" ); document.write( "Use eq. 2 to substitute 2N for Q in eq. 3\r\n" ); document.write( "\r\n" ); document.write( "3. D = Q + 1\r\n" ); document.write( "4. D = 2N + 1\r\n" ); document.write( "\r\n" ); document.write( "Use eq. 2 to substitute 2N for Q in eq. 1 and\r\n" ); document.write( "use eq. 4 to substitute 2N + 1 for D in eq 1:\r\n" ); document.write( "\r\n" ); document.write( "1. 5Q + 2D + N = 122\r\n" ); document.write( " 5(2N) + 2(2N + 1) + N = 122 \r\n" ); document.write( " 10N + 4N + 2 + N = 122\r\n" ); document.write( " 15N + 2 = 122\r\n" ); document.write( " 15N = 120\r\n" ); document.write( " N = 8\r\n" ); document.write( "\r\n" ); document.write( "Substitute 8 for N in eq. 4:\r\n" ); document.write( "\r\n" ); document.write( "4. D = 2N + 1\r\n" ); document.write( " D = 2(8) + 1\r\n" ); document.write( " D = 16 + 1\r\n" ); document.write( " D = 17\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Substitute N=8 in eq. 2\r\n" ); document.write( "\r\n" ); document.write( "2. Q = 2N\r\n" ); document.write( " Q = 2(8)\r\n" ); document.write( " Q = 16\r\n" ); document.write( "\r\n" ); document.write( "Edwin\n" ); document.write( " |