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.

Ex Input:
There were 28 bales of hay in the barn . Tim stacked bales in the barn today . There are now 54 bales of hay in the barn . How many bales did he store in the barn ?

Ex Output:
26

Ex Input:
A pet shelter had 9 puppies when another 12 were brought in . If 3 puppies a day are adopted , how long would it take for all of them to be adopted ?

Ex Output:
7

Ex Input:
Ceasar needs to read a 563 page book for school . He has already read 147 pages . How many pages does he have left to read ?

Ex Output:
416