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: Charles has 25 Skittles . Diana takes 7 away . How many Skittles will Charles have ?
Example Output: 18

Example Input: Sara has 31 red and 15 green balloons . Sandy has 24 red balloons . How many red balloons do they have in total ?
Example Output: 55

Example Input: Jonathan wants to buy a dictionary that costs $ 11 , a dinosaur book that costs $ 19 , and a children 's cookbook that costs $ 7 . He has saved $ 8 from his allowance . How much more money does Jonathan need to buy all three books ?
Example Output:
29