document.write( "Question 1003706: Anne and Maria play tennis almost every weekend. So far, Anne has won 12 out of 20 matches. \r
\n" ); document.write( "\n" ); document.write( "How many matches will Anne have to win in a row to improve her winning percentage to 75%?\r
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Algebra.Com's Answer #620347 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
Anne and Maria play tennis almost every weekend. So far, Anne has won 12 out of 20 matches.
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\n" ); document.write( "How many matches will Anne have to win in a row to improve her winning percentage to 75%?
\n" ); document.write( "Let number of new wins be \"x\"::
\n" ); document.write( "(12+x)/(12+20+x) = = 0.75
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\n" ); document.write( "(12+x)/(32+x) = (3/4)
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\n" ); document.write( "4(12+x) = 3(32+x)
\n" ); document.write( "48 + 4x = 96 + 3x
\n" ); document.write( "x = 48 (number of new wins)
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\n" ); document.write( "How many matches will Anne have to win in a row to improve her winning percentage to 90%?
\n" ); document.write( "(12+x)/(32+x) = 0.9
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\n" ); document.write( "10(12+x) = 9(32+x)
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\n" ); document.write( "120 + 10x = 288 + 9x
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\n" ); document.write( "x = 68 (number of new wins)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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