A pupil's marks were wrongly entered as 83 instead of 63. Due to that the average marks for the class got increased by half (1/2). The number of pupils in the class is:
Choose the correct answer
A) 38  B) 39  C) 40  D) 46  E) 49
Let there be x pupils in the class.   Total increase in marks = (x x 1/2) = x/2   x /2 = (83 - 63)   x /2= 20   x= 40   Answer is 40
<result>C</result>
A pupil's marks were wrongly entered as 83 instead of 63. Due to that the average marks for the class got increased by half (1/2). The number of pupils in the class is: