Question 52263
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If he needs a final average of 90%, then over 4 exams, he must have accumulated 360 out of the possible 400 marks.

He has already done 3 exams with an average of 87%, which is 261 marks (87 x 3).

He wants 360, he has 261. Hence, he needs 99 marks in his last exam to get the 90% average.


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