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: The school cafeteria ordered 37 red apples and 45 green apples for students lunches . But , if only 51 students wanted fruit , how many extra did the cafeteria end up with ?
Example Output: 31

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: Kristi jogged for 0.6 of an hour , swam for 0.5 of an hour , and rode her bicycle for 0.75 of an hour . How long did she exercise ?
Example Output:
1.85