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.
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Question: Context: A grocery store had 81 bottles of regular soda, 60 bottles of diet soda and 60 bottles of lite soda. 

 Question: How many more bottles of regular soda did they have than diet soda?

Answer: 21


Question: Context: Ed had 2 more marbles than Doug. Doug lost some of his marbles at the playground. Now Ed has 19 more marbles than doug. 

 Question: How many marbles did Doug lose?

Answer: 17


Question: Context: Julia played tag with 8 kids on monday, 11 kids on tuesday and 9 kids on wednesday. 

 Question: How many more kids did she play with on tuesday than on wednesday?

Answer:
2