Question
The marks of a student were entered as 88 instead of 68.
Due to this, the average marks of the class increased by 0.5. What is the number of students in the class?Solution
To find the number of students n: The error increased total marks by 88-68 = 20. This caused an average increase of 0.5 marks per student. ATQ- 0.5× n = 20. n= 20/0.5 = 40. Thus, the number of students is 40
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