The average marks of 13 students was 130. But later it was found that the score of one student was wrongly entered as 23 instead of 32. What is the correct average of their score?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 130.69.
We know that,
Average = Sum of observations/Number of observations
The sum of the marks of 13 students = 13 × 130 = 1690
But later it was found that the score of one student was wrongly entered as 23 instead of 32
Actual sum = 1690 - 23 + 32 = 1699
Correct average = 1699/13 = 130.69