The average marks obtained by 60 students in a certain examination are 35. If the average marks of the students who passed are 39, and that of the students who failed are 15, how many students passed the examination?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e 50.
Let passed = x , so failed = 60 − x
Total marks = 60 × 35 = 2100
39x + 15(60 − x) = 2100
39x + 900 −15x = 2100
24x = 1200
x = 50