document.write( "Question 121698: A mother is four times as old as her daughter. In 20 years she will be twice as old as her daughter. How old are mother and daughter now? \n" ); document.write( "

Algebra.Com's Answer #89343 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"m\"$ = Mother's age now
\n" ); document.write( "Let $\"d\"$ = daughter's age now
\n" ); document.write( " $\"m+=+4d\"$
\n" ); document.write( "Read the 2nd part as: When both Mother and Daughter are
\n" ); document.write( "20 years older, The mother will be twice as old
\n" ); document.write( " $\"m+%2B+20+=+2%28d+%2B+20%29\"$
\n" ); document.write( "Substitute 1st equation into 2nd
\n" ); document.write( " $\"4d+%2B+20+=+2d+%2B+40\"$
\n" ); document.write( " $\"2d+=+20\"$
\n" ); document.write( " $\"d+=+10\"$ daughter's age now
\n" ); document.write( " $\"m+=+4d\"$
\n" ); document.write( " $\"m+=+40\"$ mother's age now
\n" ); document.write( "check:
\n" ); document.write( " $\"m+%2B+20+=+2%28d+%2B+20%29\"$
\n" ); document.write( " $\"40+%2B+20+=+2%2810+%2B+20%29\"$
\n" ); document.write( " $\"60+=+2%2A30\"$
\n" ); document.write( " $\"60+=+60\"$
\n" ); document.write( "OK \n" ); document.write( "

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