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: Zachary did 15 push-ups in gym class today. David did 39 more push-ups than Zachary. John did 9 push-ups less than David.

Question: How many more push-ups did Zachary do than John?
[EX A]: 30

[EX Q]: Context: At the arcade Dave had won 19 tickets. If he used 12 to buy some toys and 7 more to buy some clothes

Question: How many more tickets did Dave use to buy toys than he did to buy clothes?
[EX A]: 5

[EX Q]: Context: Jack received 3 emails in the afternoon, 5 emails in the morning and 16 emails in the evening.

Question: How many more emails did Jack receive in the morning than in the afternoon?
[EX A]:
2