You are given a math word problem and you are supposed to apply multiple mathematical operators like addition, subtraction, multiplication or division on the numbers embedded in the text to answer the following question and then only report the final numerical answer.

[Q]: A magician was selling magic card decks for 9 dollars each . If he started with 12 decks and by the end of the day he had 7 left , how much money did he earn ?
[A]: 45

[Q]: A magician was selling magic card decks for 5 dollars each . If he started with 14 decks and by the end of the day he had 5 left , how much money did he earn ?
[A]: 45

[Q]: Luke was selling his old games . He started out with 39 but sold 19 of them . He packed the rest up putting 4 games into each box . How many boxes did he have to use ?
[A]:
5