document.write( "Question 843199: Find the largest two digit integer that is increased by 75% when it's digits are reversed. \n" ); document.write( "
Algebra.Com's Answer #507995 by Theo(13342)![]() ![]() You can put this solution on YOUR website! let your digits be a and b.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your first number is ab. \n" ); document.write( "your second number is ba.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the value of your first number is 10a + b \n" ); document.write( "the value of your second number is 10b + a.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "assume that your second number is 75% bigger than your first number.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "this means that your second number is 1.75 times as big as your first number.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "since the value of your first number is 10a + b and the value of your second number is 10b + a, this means that:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "10b + a is equal to 1.75 * (10a + b)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "simplify this equation to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "10b + a = 17.5 * a + 1.75 * b\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "subtract 1.75 * b from both sides of this equation and subtract a from both sides of this equation to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "10b - 1.75b = 17.5a - a\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "simplify this to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "8.25b = 16.5a\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "divide both sides of this equation by 8.5 to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "b = 16.5a/8.25\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "this simplifies to b = 2a\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "since b has to be an integer, and b has to be 2a, then the biggest that b can be is 8.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "if it were 9, than a would not be an integer.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "it can't be 10 since a single digit can only go up to 9.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "so the biggest that b can be is 8 and this means that the biggest that a can be is 4 which is 1/2 * b.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "since your first number is ab, then that number is 48. \n" ); document.write( "since your second number is ba, then that number is 84.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "84 is 1.75 * 48 so the solution is good.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |