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

Example Input: Context: Haley grew 14 trees in her backyard. After a typhoon 9 died. 

 Question: How many more trees died in the typhoon than those that survived?
Example Output: 4

Example Input: Context: The school is planning a field trip. The school has 102 classrooms. There are 11 students in the school and 99 seats on each school bus. If 8 students do n't want to go for the trip 

 Question: How many students are going on the trip?
Example Output: 3

Example Input: Context: Dave had 10 apps on his phone. He added 11 new apps. After deleting some he had 4 left. 

 Question: How many apps did he delete?
Example Output:
17