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.

Q: Context: Julia played tag with 5 kids on tuesday. She had played tag with 6 kids on monday. 

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

A: 1
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Q: Context: A waiter had 13 customers. After some left he got 4 new customers. If he still had 9 customers 

 Question: How many customers left?

A: 8
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Q: Context: Winter is almost here and most animals are migrating to warmer countries. There were 87 bird families living near the mountain. If 7 bird families flew away for winter 

 Question: How many more bird families stayed behind than those that flew away for the winter?

A:
73
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