Question

The average of your 3 quiz grades is 17 points. Two of your quiz grades are 14 points and 19 points. Write and solve an equation to find the score of your third quiz.

Answer 1

The equation required is
`17=(14+19+Grade \ of \ Quiz \ 3)/(3)` and Grade of quiz 3 is 18

Explanation:

We are given

Average of 3 quiz grades = 17

Grade of quiz 1 = 14

Grade of quiz 2 = 19

We need to find Grade of quiz 3

The formula used will be:
`Average \ of \ 3 \ quiz \ grades = (Grade \ of \ Quiz \ 1+Grade \ of \ Quiz \ 2+Grade \ of \ Quiz \ 3)/(3)`

Using formula and finding the grade of quiz 3

`Average \ of \ 3 \ quiz \ grades = (Grade \ of \ Quiz \ 1+Grade \ of \ Quiz \ 2+Grade \ of \ Quiz \ 3)/(3)\\17=(14+19+Grade \ of \ Quiz \ 3)/(3) \\17*3=14+19+Grade \ of \ Quiz \ 3\\51=33+Grade \ of \ Quiz \ 3\\Grade \ of \ Quiz \ 3=51-33\\Grade \ of \ Quiz \ 3=18`

So, The equation required is
`17=(14+19+Grade \ of \ Quiz \ 3)/(3)` and Grade of quiz 3 is 18