document.write( "Question 522491: My son has a math worksheet that he needs to score at least 90% on. It has 12 problems on it. How do we figure how many problems he has to get right in order to score at least 90%? \n" ); document.write( "
Algebra.Com's Answer #346875 by oberobic(2304)\"\" \"About 
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Assuming there are a total of 100 points, 100/12 = 8 1/3 points per answer.
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\n" ); document.write( "To score at least 90, means 90 or more.
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\n" ); document.write( "x = number of correct answers
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\n" ); document.write( "100/12*x >= 90
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\n" ); document.write( "100x = 1080
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\n" ); document.write( "x = 10.8
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\n" ); document.write( "Assuming you can only get full credit for an answer or no credit, then your son must get at least 11 of the 12 questions right to have a score of 90% or higher.
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\n" ); document.write( "Done.
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