If the average marks of three batches of 40, 50 and 60 students, respectively, is 50, 60 and 75, then the average marks of all the students is:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 63.33.
Total marks of all the students = (40 × 50) + (50 × 60) + (60 × 75)
⇒ 2000 + 3000 + 4500 = 9500
Total number of students in three batches = 40 + 50 + 60 = 150
Now, required average = 9500/150 = 63.33