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 worksheet had 7 problems on it . If a teacher had 17 worksheets to grade and had already graded 8 of them , how many more problems does she have to grade ?
Example Output: 63

Example Input: Luke made 9 dollars mowing lawns and 18 dollars weed eating . If he only spent 3 dollar a week , how long would the money last him ?
Example Output: 9

Example Input: A pet store had 102 puppies . In one day they sold 21 of them and put the rest into cages with 9 in each cage . How many cages did they use ?
Example Output:
9