Question

Aaron has a $450 gift card from a clothing store spent a total of $28 so far she wants to buy the barrettes for $2.95 each how many barrettes you by without going over the limit of the card

Answer 1

You know that $28 was spent on the card already, so subtract that from the total:
450-28=422

There is $422 on the card. If each barrette costs $2.95, you can divide the money left on the card by how much the barrettes cost:
422/2.95=143.05

You can by 143 barrettes without going over the limit.