You are given a math word problem and you are supposed to apply addition or subtraction mathematical operators on the numbers embedded in the text to answer the following question and then only report the final numerical answer.

Q: A waiter at ' The Greasy Spoon ' restaurant had 29 customers to wait on . During the lunch rush he added another 20 customers . If 34 of the customers did n't leave him a tip , how many customers did leave a tip ?

A: 15
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Q: Tim 's cat had kittens . He gave 3 to Jessica and 6 to Sara . He now has 9 kittens . How many kittens did he have to start with ?

A: 18
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Q: Joyce starts with 75 apples . She gives 52 to Larry . How many apples does Joyce end with ?

A:
23
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