document.write( "Question 662581: My age is now 4 times his. Twenty years later his wil be half mine. How old are we now? \n" ); document.write( "

Algebra.Com's Answer #412895 by kevwill(135) $\"\"$ $\"About$

You can put this solution on YOUR website!
I think the original solver got this one wrong.
\n" ); document.write( "Let m = my age now, and h = his age now. My age is now 4 times is, so:
\n" ); document.write( " $\"m+=+4%2Ah%29\"$
\n" ); document.write( "Twenty years later, his will be half mine, so:
\n" ); document.write( " $\"%28m%2B20%29%2F2+=+h+%2B+20\"$
\n" ); document.write( "Substituting 4*h for m (from the first equation) gives:
\n" ); document.write( " $\"%284%2Ah+%2B+20%29%2F2+=+h+%2B+20\"$
\n" ); document.write( " $\"2%2Ah+%2B+10+=+h+%2B+20\"$
\n" ); document.write( "Subtracting h + 10 from each side gives:
\n" ); document.write( " $\"2%2Ah+%2B+10+-+%28h+%2B+10%29+=+h+%2B+20+-+%28h+%2B+10%29\"$
\n" ); document.write( " $\"2%2Ah+%2B+10+-+h+-+10+=+h+%2B+20+-+h+-+10\"$
\n" ); document.write( " $\"h+=+10\"$
\n" ); document.write( "So his age is currently 10 and mine is 40.
\n" ); document.write( " \n" ); document.write( "

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