document.write( "Question 1032946: Jean is three times as old as her sister. In 6 years time she will be twice as old as her sister how old is jean \n" ); document.write( "

Algebra.Com's Answer #647528 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+a+\"$ = Jean's age now
\n" ); document.write( "Let $\"+b+\"$ = her sister's age now
\n" ); document.write( "----------------------------
\n" ); document.write( "(1) $\"+a+=+3b+\"$
\n" ); document.write( "(2) $\"+a+%2B+6+=+2%2A%28+b+%2B+6+%29+\"$
\n" ); document.write( "------------------------
\n" ); document.write( "Substitute (1) into (2)
\n" ); document.write( "(2) $\"+3b+%2B+6+=+2%2A%28+b+%2B+6+%29+\"$
\n" ); document.write( "(2) $\"+3b+%2B+6+=+2b+%2B+12+\"$
\n" ); document.write( "(2) $\"+b+=+6+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+a+=+3b+\"$
\n" ); document.write( "(1) $\"+a+=+3%2A6+\"$
\n" ); document.write( "(1) $\"+a+=+18+\"$
\n" ); document.write( "----------------
\n" ); document.write( "Jean is 18
\n" ); document.write( "--------------
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+a+%2B+6+=+2%2A%28+b+%2B+6+%29+\"$
\n" ); document.write( "(2) $\"+18+%2B+6+=+2%2A%28+6+%2B+6+%29+\"$
\n" ); document.write( "(2) $\"+24+=+2%2A12+\"$
\n" ); document.write( "(2) $\"+24+=+24+\"$
\n" ); document.write( "OK \n" ); document.write( "

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