In an examination, the average score of a student was 67.6. If he would have got 27 more marks in Mathematics, 10 more marks in Computer Science, 18 more marks in History and retained the same marks in other subjects, then his average score would have been 72.6. How many papers were there in the examination?

11

Used Formula - Δ Total = Δ Avg. x Number of item

Total change in marks = 27 + 18 + 10 = 55

Change in avg. = 72.6- 67.6 =5

Number of Subject = 11