document.write( "Question 1164209: Susan cashed a check at the bank, but the teller made a mistake. He gave her as many dollars as he should have given her cents and as many cents as he should have given her dollars. Susan took the money without realizing the error and spent $3.50. She then had twice as much money as the actual amount of the check. What was the amount of the check? \n" ); document.write( "
Algebra.Com's Answer #788743 by ikleyn(52811)![]() ![]() You can put this solution on YOUR website! .\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "For linear Diophantine equations (one equation with integer coefficients for two integer unknowns) the trial an error method \r \n" ); document.write( "\n" ); document.write( "finding a solution is absolutely and totally LEGAL (and standard) method.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "For such equations, any version of trial and error search is ALLOWABLE, and nobody of mature mathematicians \r \n" ); document.write( "\n" ); document.write( "do not really care by WHICH concretely searching method the solution is obtained.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "You may use an Excel table/spreadsheet for it and to find the solution in seconds (as I usually do it . . . )\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Nobody cares about it . . . \r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Or, alternatively, you can find it via 30 lines formula transformations. It is also good,\r \n" ); document.write( "\n" ); document.write( "but again, NOBODY CARES about it . . . \r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "What is REALLY IMPORTANT for such equations, it is the necessary and sufficient condition for \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "This condition REQUIRES that the right side constant term must be a MULTIPLE of the Greatest Common Divisor of the coefficients\r \n" ); document.write( "\n" ); document.write( "of the equation at \"x\" and \"y\".\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "If this condition is satisfied, then the solution DOES EXIST, and all the troubles just do stop at this point.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |