Question 1207382
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WOW! A final exam counting for 2/3 of the grade for the course? Scary....<br>
The average of his four test scores is {{{(86+80+84+90)/4=85}}}<br>
To get a B, his overall average has to be 80.  That is 5 points below the average of his test scores.  The final exam counts for 2/3 of the total grade, which means it counts for twice as much as his current test average.  So his score on the final exam has to be 5/2 = 2.5 points below 80 -- i.e., 77.5.<br>
ANSWER #1: to get a B (average of 80), his score on the final exam needs to be 77.5<br>
Similarly, to get an A in the course he needs an average of 90; his current test score average is 5 points below 90, so his score on the final exam needs to be 5/2 = 2.5 points above 90.<br>
ANSWER #2: to get a A (average of 90), his score on the final exam needs to be 92.5<br>