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.

Example Input: a magician was selling magic card decks for 2 dollars each . if he started with 5 decks and by the end of the day he had 3 left how much money did he earn ?
Example Output: 4

Example Input: a chef only had 3 apples so he ordered 2 more bags . if each bag has 9 apples how many apples does he have total ?
Example Output: 21

Example Input: lex read a 420 page book about music and instruments . if he can read exactly 30 pages a day how many days will it take lex to finish reading the book ?
Example Output:
14