Question

In a class, \( 25 \% \) of the students were absent for an exam. \( 30 \% \) failed by 20 marks and \( 10 \% \) just passed because of grace marks of 5 . Find the average score of the class if the remaining students scored an average of 60 marks and the pass marks are 33 (counting the final scores of the candidates). (a) 37.266 (b) 37.6 (c) 37.8 (d) 36.93

Answer 1

Answer: (b) 37.6

Let say There were  100S  students

Absent = (25/100)100S = 25S

Score by 25S students = 0   ( as absent)

30% failed by 20 marks

so marks received by them = 33 - 20 = 13

30% Students = (30/100)100S = 30S

Score by 30S Students = 30S * 13 = 390S

10% Students = 10S

Just passed because of grace Mark = 5

so their score = 33   ( final score to be counted)

Score by 10S Students = 10S * 33 = 330S

Remaining Students = 100S - 25S - 30S - 10S = 35S

Average of remaining = 60

Score by remaining 35S Students = 35S  * 60 - 2100S

Total Score = 0 + 390S + 330S + 2100S  = 2820 S

Average = 2820S/100S  = 28.2

Average of Appeared students  = 2820S/75S  = 37.6