The task is to generate the correct answer for a given math problem.
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Question: Problem: what is the greatest prime factor of 2 ^ 10 - 1 ?

Answer: 3


Question: Problem: a man buys 60 pens at marked price of 46 pens from a whole seller . if he sells these pens giving a discount of 1 % , what is the profit percent ?

Answer: 29.13 %


Question: Problem: a man swims downstream 40 km and upstream 16 km taking 4 hours each time , what is the speed of the man in still water ?

Answer:
7.5