document.write( "Question 498809: Two years ago, a man was eight times as old as his son. In three years time, he will be four and half times his son's age then. Find their present ages. \n" ); document.write( "
Algebra.Com's Answer #338042 by Maths68(1474)\"\" \"About 
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Let
\n" ); document.write( "Present age of father = f
\n" ); document.write( "Present age of son = s\r
\n" ); document.write( "\n" ); document.write( "Two years ago means we have to subtract 2 from their present ages
\n" ); document.write( "f-2=s-2
\n" ); document.write( "then
\n" ); document.write( "father was eight times as old as his son
\n" ); document.write( "f-2=8(s-2)
\n" ); document.write( "f-2=8s-16
\n" ); document.write( "f=8s-16+2
\n" ); document.write( "f=8s-14..................(1)
\n" ); document.write( "In three years time means we have add 3 in their present ages
\n" ); document.write( "f+3=s+3
\n" ); document.write( "then he will be four and half times his son's age
\n" ); document.write( "f+3=(4.5)(s+3)
\n" ); document.write( "f+3=4.5s+13.5
\n" ); document.write( "f=4.5s+13.5-3
\n" ); document.write( "f=4.5s+10.5 ........(2)
\n" ); document.write( "Put the value of f from (1) to (2)
\n" ); document.write( "f=4.5s+10.5 ........(2)
\n" ); document.write( "8s-14=4.5s+10.5
\n" ); document.write( "8s-4.5s=10.5+14
\n" ); document.write( "3.5s=24.5
\n" ); document.write( "Divide both sides of above equation by 3.5
\n" ); document.write( "3.5s/3.5 = 24.5/3.5
\n" ); document.write( "s=7
\n" ); document.write( "plug in the value of s in equation (1)
\n" ); document.write( "f=8s-14..................(1)
\n" ); document.write( "f=8(7)-14
\n" ); document.write( "f=56-14
\n" ); document.write( "f=42
\n" ); document.write( "Present age of father = 42
\n" ); document.write( "Present age of son = 7\r
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