document.write( "Question 892267: How many 75%(c) grades does it take to bribg a zero up to a C(>70%) \n" ); document.write( "

Algebra.Com's Answer #540418 by KMST(5328) $\"\"$ $\"About$

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If all grades count the same (for example, if the grades are for quizzes given equal value for the average), after a zero, $\"n\"$ 75%(c) grades would bring the average percentage grade to
\n" ); document.write( " $\"%2875%2An%2B0%29%2F%28n%2B1%29=75n%2F%28n%2B1%29\"$ %
\n" ); document.write( "for a 70.00%, we need $\"75n%2F%28n%2B1%29=70\"$ .
\n" ); document.write( "Solving that equation:
\n" ); document.write( " $\"75n%2F%28n%2B1%29=70\"$ --> $\"75n=70%28n%2B1%29\"$ --> $\"75n=70n%2B70\"$ --> $\"75n-70n=70\"$ --> $\"5n=70\"$ --> $\"n=70%2F5\"$ --> $\"highlight%28n=14%29\"$ .
\n" ); document.write( "In practice, $\"highlight%2813%29\"$ 75%(c) grades would do,
\n" ); document.write( "because a 69.50% would be rounded to 70%, and the equation would be
\n" ); document.write( " $\"75n%2F%28n%2B1%29=69.5\"$ --> $\"75n=69.5%28n%2B1%29\"$ --> $\"75n=69.5n%2B69.5\"$ --> $\"75n-69.5n=69.5\"$ --> $\"5.5n=69.5\"$ --> $\"n=69.5%2F5.5\"$ --> $\"n=about+12.64\"$ . \n" ); document.write( "

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