Arithmetic mean

Question

My mean mark in six test is 9.if in the next two tests, i scored 6 and 4. What is my new average.

Answer 1

(9*6 +6+4) / 8= 64/8 = 8

Answer 2

Since you know you have a mean of 9 on the previous 6 tests, we will assign each of those tests a score of 9.

The other two test scores are given.

To find a mean, you need to add the scores and then divide that sum by the number of scores you added.

9 + 9 + 9 + 9 + 9 + 9 + 6 + 4 = 64

64 divided by 8 = 8