document.write( "Question 935758: Jane averaged her five equally weighted test grades and got 60%. This was wrong because she had entered one grade incorrectly. That incorrect score should have been entered as 80%. If she had used the 80%, her correct average for the five tests would have been 70%. What percent did she incorrectly enter instead of 80%? \n" ); document.write( "

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Jane averaged her five equally weighted test grades and got 60%. This was wrong because she had entered one grade incorrectly. That incorrect score should have been entered as 80%. If she had used the 80%, her correct average for the five tests would have been 70%. What percent did she incorrectly enter instead of 80%?
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\n" ); document.write( "Equations:
\n" ); document.write( "4correct scores and 1 error score::
\n" ); document.write( "(4c + e)/5 = 60
\n" ); document.write( "4c + e = 300
\n" ); document.write( "-----------------------
\n" ); document.write( "5 correct scores::
\n" ); document.write( "(4c + 80)/5 = 70
\n" ); document.write( "4c + 80 = 350
\n" ); document.write( "-------
\n" ); document.write( "Solve this system:
\n" ); document.write( "4c + e = 300
\n" ); document.write( "4c + 80 = 350
\n" ); document.write( "-----
\n" ); document.write( "80-e = 50
\n" ); document.write( "e = 30
\n" ); document.write( "-----
\n" ); document.write( "Answer:: 30%
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "

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