He bought a package of pencils for $2.99 and some erasers that cost $0.33 each. The total amount she paid for these items is $4.97.
total cost of pencil = $2.99
cost of each eraser = $0.33
Total cost of items = $4.97
let
the number of eraser = x
The equation can be represented below

She bought 6 eraser altogether.