document.write( "Question 479604: Seven years ago, Mary was six times as old as Cora. In one year, she will only be twice as old as Cora. Find their present ages. \n" ); document.write( "
Algebra.Com's Answer #330108 by Maths68(1474)\"\" \"About 
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Mary’s age = M
\n" ); document.write( "Cora’s age = C\r
\n" ); document.write( "\n" ); document.write( "Seven year ago means we have to subtract 7 from Mary and Cora’s age\r
\n" ); document.write( "\n" ); document.write( "M-7=6(C-7)
\n" ); document.write( "M-7=6C-42
\n" ); document.write( "M=6C-42+7
\n" ); document.write( "M=6C-35……………..(1)\r
\n" ); document.write( "\n" ); document.write( "In one year means we have to add one years in Mary and Cora’s age
\n" ); document.write( "M+1=2(C+1)
\n" ); document.write( "M+1=2C+2
\n" ); document.write( "M=2C+2-1
\n" ); document.write( "M=2C+1………….(2)\r
\n" ); document.write( "\n" ); document.write( "Subtract (2) from (1)\r
\n" ); document.write( "\n" ); document.write( "M=6C-35
\n" ); document.write( "-M=-2C-1
\n" ); document.write( "------------
\n" ); document.write( "0=4C-36\r
\n" ); document.write( "\n" ); document.write( "4C=36
\n" ); document.write( "C=36/4
\n" ); document.write( "C=9\r
\n" ); document.write( "\n" ); document.write( "Put the value of C in equation (1)
\n" ); document.write( "M=6C-35
\n" ); document.write( "M=6(9)-35
\n" ); document.write( "M=54-35
\n" ); document.write( "M=19\r
\n" ); document.write( "\n" ); document.write( "Mary is 19 years old
\n" ); document.write( "Cora is 9 years old
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