document.write( "Question 935100: There are 20 true/false questions and 20 multiple choice questions on a test.\r
\n" ); document.write( "\n" ); document.write( "A correct answer to a true false question earns 10 points. \r
\n" ); document.write( "\n" ); document.write( "A correct answer to a multiple choice question earns 12 points.\r
\n" ); document.write( "\n" ); document.write( "The test makers determined that it takes, on average 3 minutes to answer a true/false question and 4 minutes to answer a multiple choice question. Students have 1 hour to answer to answer at most 18 questions of their choice. How many of each kind of question should a student answer correctly to get the greatest possible score?
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Algebra.Com's Answer #568246 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
There are 20 true/false questions and 20 multiple choice questions on a test.
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\n" ); document.write( "A correct answer to a true false question earns 10 points.
\n" ); document.write( "A correct answer to a multiple choice question earns 12 points.
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\n" ); document.write( "The test makers determined that it takes, on average 3 minutes to answer a true/false question and 4 minutes to answer a multiple choice question.
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\n" ); document.write( "Students have 1 hour to answer at most 18 questions of their choice. How many of each kind of question should a student answer correctly to get the greatest possible score?
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\n" ); document.write( "t + m <= 18 questions
\n" ); document.write( "3t + 4m <= 60 minutes
\n" ); document.write( "Objective Rule:: Score = 10t + 12m
\n" ); document.write( "t >= 0
\n" ); document.write( "m >= 0
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\n" ); document.write( "Graph::
\n" ); document.write( "t = -m + 18 and shade the area below it in QI
\n" ); document.write( "t = (-4/3)m + 20 and shade the area below it in QI
\n" ); document.write( "\"graph%28400%2C400%2C-5%2C40%2C-5%2C30%2C-x%2B18%2C%28-4%2F3%29x%2B20%29\"
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\n" ); document.write( "Find the intercepts and the intersection of the 2 lines.
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\n" ); document.write( "(0,18) and (18,0) for t = -m+18
\n" ); document.write( "(0,20) and (15,0) for t = (-4/3)m+20
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\n" ); document.write( "Find the intersection of the 2 lines:
\n" ); document.write( "-m+18 = (-4/3)m + 20
\n" ); document.write( "(1/3)m = 2
\n" ); document.write( "m = 6 ; and t = -m+18, so t = 12
\n" ); document.write( "Intersection:: (6,12)
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\n" ); document.write( "Substitute the proper point coordinates into the Objective Function
\n" ); document.write( "to determine which combination of t(true/false) and m(multiple choice)
\n" ); document.write( "gives a maximum value.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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