Question

The average marks scored by Aswin in certain number of test is 84. He scored 100 marks in the next test.
His new average score of all those tests is 86, then the total number of tests he appeared, is
A 8
B) 7
C) 5
D) 10​

Answer 1

Answer:

8

Step-by-step explanation:

Let the average marks of n test is 84.

Total marks of n test=84n

Marks in (n+1)th test =100

Total marks in (n+1) test=84n+100

Average marks in (n+1) test=84n+100/n+1

⇒86=84n+100/n+1

⇒86n+86=84n+100

⇒86n−84n=100−86

⇒2n=14

⇒n=7

Total number of test=n+1=7+1=8

Hope it helps you!