John's marks wrongly entered as 82 instead of 62. Due to that the average marks for the class got increased by half (1/2). The number of John in the class is?	Choose the most appropriate option:
A) 70
B) 78
C) 80
D) 84
E) 90
otal increase in marks = x x	1 =	x   2	2   x/2	= (82 - 62) x/2	= 40 x= 80.   80
<result>C</result>
John's marks wrongly entered as 82 instead of 62. Due to that the average marks for the class got increased by half (1/2). The number of John in the class is?