A learner's marks in 4 tests are 65, 70, 81, 82. What mark is needed in the next test for the average of all 5 tests to be 65?
Answer and explanation
Correct answer: C. 27
- Step 1: Total needed for 5 tests = 65 × 5 = 325.
- Step 2: Marks so far = 298, so the next mark must be 325 - 298 = 27.
Answer
27.
Why not the others: 65: the target average was given as the missing mark. 22: this mark leaves the average of all the tests below the target. 37: this mark pushes the average above the target.
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