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.
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Question: Tom had to wash 10 short sleeve shirts and 25 long sleeve shirts before school . If he had only washed 5 of them by the time school started , how many did he not wash ?

Answer: 30


Question: There are 79 pencils in a box . Eric takes 4 pencils . How many are left ?

Answer: 75


Question: A cell phone company has a total of 7422 customers across the world . If 723 of its customers live in the United States , how many of its customers live in other countries ?

Answer:
6699