Correct Answer - Option 2 : 72.2
Given:
The average marks of student in 5 subjects are 70.
Formula used:
Sum of observations = average × numbers of observations
Calculation:
Sum of all numbers = 70 × 5 = 350
Later, marks in one subject were increased by 19.5 and marks in another subject were decreased by 8.5.
∴ Correct marks = 350 + 19.5 – 8.5 = 361
Correct Average = Correct sum / number = 361 / 5 = 72.2