document.write( "Question 257556: A student scores 75, 86, and 72 on three 100-point exams. If the final is worth 150 points, find the range of final exam score,S, that gives the student an overall percentage of 80% or higher. This is as far as I could get.\r
\n" ); document.write( "\n" ); document.write( "x= final exam score
\n" ); document.write( "S(x)= final average if final exam score is x\r
\n" ); document.write( "\n" ); document.write( "Not sure where to go from here. None of the answers I come up with make sense. Please help. \n" ); document.write( "

Algebra.Com's Answer #189460 by stanbon(75887) $\"\"$ $\"About$

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A student scores 75, 86, and 72 on three 100-point exams. If the final is worth 150 points, find the range of final exam score,S, that gives the student an overall percentage of 80% or higher.
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\n" ); document.write( "Total # of possible points = 3*100+150 = 450
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\n" ); document.write( "80% of 450 = 360
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\n" ); document.write( "The student has 75+86+72 = 233 points from the 1st 3 exams.
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\n" ); document.write( "Ans: 360-233 <= S <= 150
\n" ); document.write( "127 <= S <= 150
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "

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