document.write( "Question 763410: My father is currently 13 times as old as my daughter. Next year, my father will be 11 times as old as my daughter. How many years old is my father now?
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Algebra.Com's Answer #464781 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+f+\"$ = my father's age now
\n" ); document.write( "Let $\"+d+\"$ = my daughter's age now
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\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+f+=+13d+\"$
\n" ); document.write( "(2) $\"+f+%2B+1++=+11%2A%28+d+%2B+1+%29+\"$
\n" ); document.write( "------------------------
\n" ); document.write( "(2) $\"+f+%2B+1+=+11d+%2B+11+\"$
\n" ); document.write( "(2) $\"+f+-+11d+=+10+\"$
\n" ); document.write( "Substitute (1) into (2)
\n" ); document.write( "(2) $\"+13d+-+11d+=+10+\"$
\n" ); document.write( "(2) $\"+2d+=+10+\"$
\n" ); document.write( "(2) $\"+d+=+5+\"$
\n" ); document.write( "and, since
\n" ); document.write( "(1) $\"+f+=+13d+\"$
\n" ); document.write( "(1) $\"+f+=+13%2A5+\"$
\n" ); document.write( "(1) $\"+f+=+65+\"$
\n" ); document.write( "My father is 65
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+f+%2B+1++=+11%2A%28+d+%2B+1+%29+\"$
\n" ); document.write( "(2) $\"+65+%2B+1++=+11%2A%28+5+%2B+1+%29+\"$
\n" ); document.write( "(2) $\"+66+=+11%2A6+\"$
\n" ); document.write( "(2) $\"+66+=+66+\"$
\n" ); document.write( "OK\r
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