SOLUTION: The average mark for 100 learners in a test is 39%. The average mark for the learners who passed is 60%, while the average mark for the learners who failed is 30%.

Question 1025086: The average mark for 100 learners in a test is 39%. The average mark for the learners who passed is 60%, while the average mark for the learners who failed is 30%. Compute the number of learners who failed the test
Answer by robertb(5830) (Show Source): You can put this solution on YOUR website!
Let = sum of averages of the passes, and = sum of the averages of the failures.
==> ==> .
Let x = number of passes, so that 100 - x = number of failures.
==> and
==> and
==> ==> x = 30, the number of passes, and
100 - x = 70, the number of failures.
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