Given a math word problem, answer the following question. You might need to apply addition or subtraction mathematical operators on the numbers embedded in the text to answer the question and then only report the final numerical answer.

Ex Input:
cheryl and lori started a lemonade stand on friday . they bought 85 plastic cups . they sold a lot of lemonade and only had 18 cups left . how many cups did cheryl and lori use ?

Ex Output:
67

Ex Input:
kaleb had 67 cherries . after eating some he had 42 left . how many cherries did kaleb eat ?

Ex Output:
25

Ex Input:
if the cave is 974 feet deep and they are already at 588 feet how much farther until they reach the end of the cave ?

Ex Output:
386