document.write( "Question 514750: joe is 9 years younger than maria. in 4 years, she will be twice as old as he will be. find their percent age? \n" ); document.write( "
Algebra.Com's Answer #343934 by Maths68(1474)\"\" \"About 
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\n" ); document.write( "Let
\n" ); document.write( "Present age of Joe = j
\n" ); document.write( "Present age of Maria = m\r
\n" ); document.write( "\n" ); document.write( "joe is 9 years younger than maria.
\n" ); document.write( "m=j+9.......(1)\r
\n" ); document.write( "\n" ); document.write( "In 4 years,
\n" ); document.write( "m+4=j+4
\n" ); document.write( "then
\n" ); document.write( "she will be twice as old as he will be
\n" ); document.write( "m+4=2(j+4)
\n" ); document.write( "m+4=2j+8
\n" ); document.write( "m=2j+8-4
\n" ); document.write( "m=2j+4
\n" ); document.write( "Put the value of m from (1) to above equation
\n" ); document.write( "j+9=2j+4
\n" ); document.write( "j-2j=4-9
\n" ); document.write( "-j=-5
\n" ); document.write( "Multiply by (-1) both sides
\n" ); document.write( "(-1)(-j)=(-1)(-5)
\n" ); document.write( "j=5\r
\n" ); document.write( "\n" ); document.write( "Put the value of j in (1)\r
\n" ); document.write( "\n" ); document.write( "m=j+9.......(1)
\n" ); document.write( "m=5+9
\n" ); document.write( "m=14\r
\n" ); document.write( "\n" ); document.write( "Present age of Joe = j = 5 years old
\n" ); document.write( "Present age of Maria = m = 14 years old
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