Question

The average marks of 42 students in an examination, was 64. Later it was found that the marks of three students were misread as 72, 58 and 44 instead of the actual marks 64, 42 and 26 respectively. What is the correct average marks?
1. 61
2. 62
3. 63
4. 60

Answer 1

Correct Answer - Option 3 : 63

Given:

The average marks of 42 students in an examination = 64

Formula Used:

Average of a given Terms/Series/Values = (Sum of the given Terms/Series/Values) / (Number of Terms/Series/Values)

Calculation:

Total Marks  = 42× 64 = 2688

⇒ Later it was found that the marks of three students were misread as 72, 58, and 44 instead of the actual marks

64, 42, and 26 respectively

∴  the Actual Average is = {2688−(72+58+44)+(64+42+26)}/42 = 63