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.

Context: Tiffany was collecting cans for recycling. On monday she had some bags of cans. The next day she found 4 more bags worth of cans. If she had a total of 8 bags altogether 

 Question: How many bags did she have on monday?
4

Context: Paul got a box of 521 crayons and 66 erasers for his birthday. At the end of the school year he only had 154 left while not having lost a single erasers. 

 Question: How many crayons had been lost or given away?
367

Context: 6 storks and 2 birds were sitting on the fence. 3 more birds came to join them. 

 Question: How many more storks than birds are sitting on the fence?

1