Question

[#] 4. 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:



a.10

Answer 1

Answer:

Number of pupils in the class=40

Step-by-step explanation:

Let the number of pupils in the class be y

Let the Correct sum of the marks be x

Let the Correct average be z

83-63=20

x/y=z,  x=yz

(x+20)/y=z+(1/2)

2x+40=2yz+y

2x+40=2x+y

y=40