A. 270
B. 275
C. 280
D. 285
Since the month begins with a Sunday, to there will be five Sundays in the month
Required average = [ (510 x 5) + (240 x 25) ] / 30
=> 8550 / 30
=> 285
If the average marks of three batches of 55, 60 and 45 students respectively is 50, 55, 60, then the average marks of all the students is:
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: