Question

the art class had a box filled with balls of yarn. the student used six and two thirds balls for a project. there are now two and two thirds left in the box. How many balls of yarn did the art class start with

Answer 1

`9(1)/(3)` (nine and one third)

Explanation:

we can represent the situation with an equation where the x represents the original number of balls of yarn.

The students used
`6(2)/(3)` so we must substract this from the number of balls of yarn x:

`x-6(2)/(3)`

and then " there are now
`2(2)/(3)` left in the box", so:

`x-6(2)/(3)=2(2)/(3)`

clearing for x:

`x=2(2)/(3)+ 6(2)/(3)\\x=8(4)/(3) \\`

and since
`(4)/(3) =1(1)/(3)`

`x=9(1)/(3)`

they started with
`9(1)/(3)` (nine and one third) balls of yarn

Answer 2

What you must do in this case is to add the number of yarn balls that the student used with the number of yarn balls that were left in the box.
Adding we have:
(6 2/3) + (2 2/3) = 8 4/3 = 9 1/3
answer
the art class start with 9 1/3 balls of yarn