Question

In a class, 20% of the students were absent for an

exam. 10% failed by 10 marks and 20% just passed

because of grace marks of 5. Find the average score

of the class if the remaining students scored an aver-

age of 50 marks and the pass marks are 30 ​

Answer 1

Answer:

Let total students be 100.

Hence, marks of 20 students is 0 as they were absent.

30 students scored 20 marks (as they failed by 20 marks)

10 students scored 40 marks (just passed)

40 students scored 65 marks (average of 65)

Therefore, average score of the class is: (0 + 600 + 400 + 2600)/100 = 3600/100

= 36

Answer 2

Answer:

33

Step-by-step explanation:

In a class, 20% of the students were absent.

20 students out of 100 scored 0

10% failed by 10 marks

10 students scored 20 (since passing marks are 30 and they failed by 10 marks)

20% just passed  because of grace marks of 5

20 students scored 30 (after including the grace marks)

50 students had an average of 50 marks.

Average of whole class is: (0 + 200 + 600 + 2500)/100 = 3300/100

Average is 33.