document.write( "Question 567475: Going into the final exams, which will count as two-thirds of the final grade, Mike has test scores of 86,80,84, and 90. What score does Mike need on the final in order to earn a B, whuch requires an average score of 80? What does he need to earn an A, which requires an average of 90? \n" ); document.write( "
Algebra.Com's Answer #366546 by lwsshak3(11628)\"\" \"About 
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Going into the final exams, which will count as two-thirds of the final grade, Mike has test scores of 86,80,84, and 90. What score does Mike need on the final in order to earn a B, which requires an average score of 80? What does he need to earn an A, which requires an average of 90?
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\n" ); document.write( "Given:
\n" ); document.write( "final exam counts as 2/3 of the final score
\n" ); document.write( "previous test scores count as 1/3 of the final score
\n" ); document.write( "let x=score needed on final to get a B or A grade
\n" ); document.write( "..
\n" ); document.write( "(86+80+84+90)/4=85 (average of previous test scores)
\n" ); document.write( "To get a B grade:
\n" ); document.write( "85/3+2x/3=80
\n" ); document.write( "85+2x=240
\n" ); document.write( "2x=240-85=155
\n" ); document.write( "x=155/2=77.5
\n" ); document.write( "..
\n" ); document.write( "To get an A grade:
\n" ); document.write( "85/3+2x/3=90
\n" ); document.write( "85+2x=270
\n" ); document.write( "2x=270-85=185
\n" ); document.write( "x=185/2=92.5
\n" ); document.write( "..
\n" ); document.write( "ans:
\n" ); document.write( "Final score needed to earn an A: 92.5
\n" ); document.write( "Final score needed to earn a B: 77.5 \n" ); document.write( "
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