document.write( "Question 8150: A man is 4 times as old as his son. Eighteen years from now, he will be only twice as old as his son. Find their present ages. \n" ); document.write( "

Algebra.Com's Answer #4484 by kritikapd(4) $\"\"$ $\"About$

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Let present age of son = X years
\n" ); document.write( "So, Present age of father = 4X years \r
\n" ); document.write( "\n" ); document.write( "Age of son after 18 years = X+18 years
\n" ); document.write( "Age of father after 18 years = 4X+18 years ……… (i)
\n" ); document.write( "Father will be twice as old his son after 18 years
\n" ); document.write( " i.e. 2 (X+18) ……….(ii)\r
\n" ); document.write( "\n" ); document.write( "Equating age of father i.e. (i) and (ii)\r
\n" ); document.write( "\n" ); document.write( "4X+18 = 2(X+18)
\n" ); document.write( "4X+18 = 2X + 36
\n" ); document.write( "4X – 2X = 36 – 18
\n" ); document.write( "2X = 18
\n" ); document.write( "X = 9 \r
\n" ); document.write( "\n" ); document.write( "So the present age of son and father is 9 years and 4 x 9= 36 years respectively.\r
\n" ); document.write( "\n" ); document.write( "Verify- Fathers age will be twice the age of son after 18 years.\r
\n" ); document.write( "\n" ); document.write( "Age of son after 18 years = 9+ 18 = 27 years
\n" ); document.write( "Age of son after 18 years = 36 + 18 = 54 years which is twice of 27 years.
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