Question

The average score for a class of 30 students is found to be 10 points better than the average score for a class size of 40. The average score for a class of 20 students is found to be 10 points better than the average score for a class size of 30. The average score for a class of 10 students is found to be 10 points better than the average score for a class size of 20. Which statement best describes the graph of average score vs class size?

Answer 1

Step-by-step explanation:

Initial Average of marks = 45

Initial sum of marks = 45×30 = 1350

After correction marks of one increased by 45 and other decreased by 15. Hence, the new sum of marks =1350+45−15=1380.

New average =

1380/30

=46.