Question

The average marks of 20 students was 45. If the marks of 10 students were taken as 40 in place of 50, find the correct average.

Answer 1

Answer:

50

Step-by-step explanation:

Average mark of 20 students=45

Total sum of marks=20*45=900

Marks of 10 students taken as 40 instead of 50

so 10 marks reduced for 10 students

Total left out mark=10*10=100

Now total sum=900+100=1000

Average of 20 students=1000/20=50

Answer 2

Answer:

Below is thee answer.

Step-by-step explanation:

Since the average of 20 students was 45, so the average will be

20 × 45 = 900

900 of 20 students

Now, if we take 40 marks in place of 50 marks for 10 students.

Since 50 - 40 = 10

Therefore

10 × 10 = 100

We will have here

800%20 = 40

40 will be the average.