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.

[EX Q]: Context: A farmer had 175 tomatoes and 77 potatoes in his garden. If he picked 172 potatoes 

 Question: How many tomatoes and potatoes does he have left?
[EX A]: 80

[EX Q]: Context: They decided to hold the party in their backyard. They have 4 sets of tables and each set has 3 chairs. If a total of 14 people will attend the party 

 Question: How many more chairs will they have to buy?
[EX A]: 2

[EX Q]: Context: There were 8 people on the bus. At the next stop 12 more people got on the bus and 3 people got off. 

 Question: How many people are there on the bus now?
[EX A]:
17