Multiple choice

The average marks, in a class of $30$ students, are found to be $45$. On checking two mistakes were found. After correction, if one student got $45$ marks more and another students got $15$ marks less, then the correct average marks are

  1. $45$
  2. $44$
  3. $47$
  4. $46$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Total marks = 30 * 45 = 1350. Net change = +45 - 15 = +30. New total = 1350 + 30 = 1380. New average = 1380 / 30 = 46.