Multiple choice

Brian obtained 70 and 75 marks in first two unit tests. Find the minimum marks that he should get in the third test to have an average of at least 60 marks.

  1. 35

  2. 60

  3. 30

  4. 36
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A Correct answer
Explanation

Average of 3 tests >= 60 implies (70+75+x)/3 >= 60. 145+x >= 180. x >= 35.

AI explanation

To achieve an average of exactly 60 marks across 3 tests, the total marks needed are 60 multiplied by 3, which equals 180. Brian's current marks add up to 70 plus 75, which is 145. Subtracting his current total from the required total gives 180 minus 145, which equals 35 marks.

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