document.write( "Question 1059955: Sally is 8 years older than john. John is 14 years older than Karen. If the sum of their ages is 90, how old are they? \n" ); document.write( "
Algebra.Com's Answer #675003 by ikleyn(52787)![]() ![]() You can put this solution on YOUR website! . \n" ); document.write( "Sally is 8 years older than john. John is 14 years older than Karen. If the sum of their ages is 90, how old are they? \n" ); document.write( "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \r\n" ); document.write( "Let K be the Karen's age.\r\n" ); document.write( "\r\n" ); document.write( "Then the John's age is (K+14) years, and Sally's age is (K+14)+8 = K + 22 years.\r\n" ); document.write( "\r\n" ); document.write( "As the condition says, the sum of ages is 90, which gives you an equation\r\n" ); document.write( "\r\n" ); document.write( "K + (K+14) + (K+22) = 90.\r\n" ); document.write( "\r\n" ); document.write( "Simplify and solve for K:\r\n" ); document.write( "\r\n" ); document.write( "3K + 36 = 90,\r\n" ); document.write( "\r\n" ); document.write( "3K = 90 - 36,\r\n" ); document.write( "\r\n" ); document.write( "3K = 54,\r\n" ); document.write( "\r\n" ); document.write( "K =\r \n" ); document.write( "\n" ); document.write( "The lesson to learn from this solution:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "1. First choose the major unknown reasonably.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "2. Second, express other unknowns via the major unknown.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "3. Then make an equation.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "4. Then solve the equation.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "It is the algorithm.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |