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

Example Input: Sara has 10 marbles . She loses 7 . How many marbles will Sara have ?
Example Output: 3

Example Input: There are 47 eggs in a box . Harry takes 5 eggs . How many are left ?
Example Output: 42

Example Input: Bianca picked 39 tulips and 49 roses to make flower bouquets . If she only used 81 of the flowers though , how many extra flowers did Bianca pick ?
Example Output:
7