Question

The average of 9 scores is x. If the tenth score is 36 points more than x, by how many points will the tenth score raise the average?

Answer 1

3.6

Explanation:

The average of 9 scores is x.

average = (sum of scores)/(number of scores)

x = (sum of scores)/9

sum of scores = 9x

The sum of the 9 scores is 9x.

The tenth score is 36 more than x, so it is x + 36.

The sum of the 10 scores is 9x + x + 36 = 10x + 36.

The average of the 10 scores is (10x + 36)/10 = x + 3.6

The difference of averages is

x + 3.6 - x = 3.6