document.write( "Question 502462: father's age was three times to his son's age. After 20 years it becomes two times. What is the age of son now? \n" ); document.write( "

Algebra.Com's Answer #338858 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"f\"$ = father's age now
\n" ); document.write( "Let $\"s\"$ = Son's age now
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+f+=+3s+\"$
\n" ); document.write( "(2) $\"+f+%2B+20+=+2%2A%28+s+%2B+20+%29+\"$
\n" ); document.write( "---------------------
\n" ); document.write( "(2) $\"+f+%2B+20+=+2s+%2B+40+\"$
\n" ); document.write( "(2) $\"+f+-+2s+=+20+\"$
\n" ); document.write( "Substitute (1) into (2)
\n" ); document.write( "(2) $\"+3s+-+2s+=+20+\"$
\n" ); document.write( "(2) $\"+s+=+20+\"$
\n" ); document.write( "The Son is now 20
\n" ); document.write( "check:
\n" ); document.write( "(1) $\"+f+=+3s+\"$
\n" ); document.write( "(1) $\"+f+=+3%2A20+\"$
\n" ); document.write( " $\"+f+=+60+\"$
\n" ); document.write( "and
\n" ); document.write( "(2) $\"+f+%2B+20+=+2%2A%28+s+%2B+20+%29+\"$
\n" ); document.write( "(2) $\"+60+%2B+20+=+2%2A%28+20+%2B+20+%29+\"$
\n" ); document.write( "(2) $\"+80+=+2%2A40+\"$
\n" ); document.write( "(2) $\"+80+=+80+\"$
\n" ); document.write( "OK \n" ); document.write( "

\n" );