document.write( "Question 518295: Jack is now 7 times as old as Jill. If 10 years from now, he will 3 years as old as Jill, how old is Jack now? \n" ); document.write( "
Algebra.Com's Answer #345122 by Maths68(1474)\"\" \"About 
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Let
\n" ); document.write( "Present age of Jack = j
\n" ); document.write( "Present age of Jill = i\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Jack is now 7 times as old as Jill.
\n" ); document.write( "j=7i.......(1)
\n" ); document.write( "If 10 years from now,
\n" ); document.write( "after 10 years Jack will be = j+10
\n" ); document.write( "after 10 years Jill will be = i+10
\n" ); document.write( "Then
\n" ); document.write( "he will 3 years as old as Jill, how old is Jack now?
\n" ); document.write( "j+10=(i+10)+3
\n" ); document.write( "j+10=i+10+3
\n" ); document.write( "j=i+10+3-10
\n" ); document.write( "j=i+3
\n" ); document.write( "Put the value of j from (1) to above equation
\n" ); document.write( "7i=i+3
\n" ); document.write( "7i-i=3
\n" ); document.write( "6i=3
\n" ); document.write( "6i/6=6/3
\n" ); document.write( "i=1/2
\n" ); document.write( "Put the value of i in (1)
\n" ); document.write( "j=7i
\n" ); document.write( "j=7 * 1/2
\n" ); document.write( "j=7/2
\n" ); document.write( "j=3.5\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Present age of Jack = j = 3 and half years old
\n" ); document.write( "Present age of Jill = i = half year old.
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