document.write( "Question 1069764: Boy is twice old as girl. If boy was two and half times as old as girl
\n" ); document.write( "Was six years ago what's their present age\r
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Algebra.Com's Answer #684885 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
Let \"+a+\" = boy's age now
\n" ); document.write( "Let \"+b+\" = girl's age now
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\n" ); document.write( "(1) \"+a+=+2b+\"
\n" ); document.write( "(2) \"+a+-+6+=+2.5%2A%28+b+-+6+%29+\"
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\n" ); document.write( "(2) \"+a+-+6+=+2.5b+-+15+\"
\n" ); document.write( "(2) \"+a+=+2.5b+-+9+\"
\n" ); document.write( "Substitute (1) into (2)
\n" ); document.write( "(2) \"+2b+=+2.5b+-+9+\"
\n" ); document.write( "(2) \"+.5b+=+9+\"
\n" ); document.write( "(2) \"+b+=+18+\"
\n" ); document.write( "and
\n" ); document.write( "(1) \"+a+=+2b+\"
\n" ); document.write( "(1) \"+a+=+2%2A18+\"
\n" ); document.write( "(1) \"+a+=+36+\"
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\n" ); document.write( "The boy is 36
\n" ); document.write( "The girl is 18
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\n" ); document.write( "(2) \"+a+-+6+=+2.5%2A%28+b+-+6+%29+\"
\n" ); document.write( "(2) \"+36+-+6+=+2.5%2A%28+18+-+6+%29+\"
\n" ); document.write( "(2) \"+30+=+2.5%2A12+\"
\n" ); document.write( "(2) \"+30+=+30+\"
\n" ); document.write( "OK
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\n" ); document.write( "I might have misread this. 36 yrs old
\n" ); document.write( "is not a boy. Get another opinion
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