Mike needs at least a 75% average to pass his math course. The class contains 5 exams that are equally weighted. If he scored a 64%, 86%, 71%, and a 90% on the first 4 exams, what score does he need on the final exam to earn at least a 75% in the class?
He needs 0.75 * 500 = 375 points
He has a total of 311 points.
375 - 311 = ?
To find out what score Mike needs on the final exam to earn at least a 75% in the class, we need to consider the weighted average of all the exams.
First, let's calculate the total marks Mike has earned so far in the class.
Mike's scores on the first 4 exams are 64%, 86%, 71%, and 90%. To find the total marks, we add these percentages together:
64% + 86% + 71% + 90% = 311%
However, since there are only 4 exams, we need to divide this total by 4 to get the average:
311% / 4 = 77.75%
So, Mike's current average is 77.75%.
To find out what score he needs on the final exam to earn at least a 75% average, we can set up the equation:
(311% + Final Exam Score) / 5 = 75%
Now, solving for the Final Exam Score:
311% + Final Exam Score = 75% * 5
311% + Final Exam Score = 375%
To isolate the Final Exam Score, we subtract 311% from both sides of the equation:
Final Exam Score = 375% - 311%
Final Exam Score = 64%
Therefore, Mike needs to score at least 64% on the final exam to earn at least a 75% average in the class.