The task is to generate the correct answer for a given math problem.
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Question: Problem: the average of first 22 natural numbers is ?

Answer: 11.5

Question: Problem: a train covers a distance of 12 km in 10 minutes . if it takes 8 seconds to pass a telegraph post , then the length of the train is

Answer: 160 m

Question: Problem: john has $ 1,600 at the beginning of his trip , after spending money , he still has exactly $ 600 less than he spent on the trip . how much money does john still have ?

Answer:
$ 50