document.write( "Question 270978: My sons math question is: Krishan wants his quiz average to be at least 90 so that he can get an A in the class. His current quiz scores are: 80, 100, 85. What does he have to get on his next quiz to have an average of 90?
\n" ); document.write( "A 85 B 90 C 92 D 95\r
\n" ); document.write( "\n" ); document.write( "I know how to solve it the long way, plugging in each number until I find the average...isn't there a short cut to it?
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Algebra.Com's Answer #198402 by vleith(2983)\"\" \"About 
You can put this solution on YOUR website!
\"Average+=+%28TotalOfAllTestScores%29%2F%28NumberOfTests%29\"
\n" ); document.write( "\"90+=+%2880%2B100%2B85%2Bx%29%2F4\"
\n" ); document.write( "\"360+=+265%2Bx\"
\n" ); document.write( "\"95+=+x\"
\n" ); document.write( "good luck Krishan
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