Correct Answer - Option 4 : 72.8
Given:
Average marks of 60 students = 72.35
Correct marks of 1 student = 81
Formula:
Average = Sum of marks/Number of students
Calculation:
Let, actual average marks of the class be x
According to the question,
60x = 60 × 72.35 + (81 – 54)
⇒ 60x = 4341 + 27
⇒ 60x = 4368
⇒ x = 4368/60
⇒ x = 72.8
∴ The actual marks of the class = 72.8