document.write( "Question 841120: When 20 boys joined a group of y students the ratio of boys to girls became 5:7 . Write an algebraic expression to represent the number of girls in terms of y. \n" ); document.write( "

Algebra.Com's Answer #506660 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+g+\"$ = the number of girls
\n" ); document.write( " $\"+y+-+g+\"$ = the original number of boys
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\n" ); document.write( "given:
\n" ); document.write( " $\"+%28+y+-+g+%2B+20+%29+%2F+g+=+5%2F7+\"$
\n" ); document.write( "Multiply both sides by $\"+7g+\"$
\n" ); document.write( " $\"+7%2A%28+y+-+g+%2B+20+%29+=+5g+\"$
\n" ); document.write( " $\"+7y+-+7g+%2B+140+=+5g+\"$
\n" ); document.write( " $\"+7y+=+12g+-+140+\"$
\n" ); document.write( " $\"+12g+=+7y+%2B+140+\"$
\n" ); document.write( " $\"+g+=+%287%2F12%29%2Ay+%2B+35%2F3+\"$ \r
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