HOW FAST - VERY FUNNY OLD MAN JOKES

A traveler walking along a road asked an old man working in a field to how long it would take to get to the next village.
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But the old man didn't answer, so the traveler kept walking.
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He hadn't gone far when he heard a call: "Hi, mister, it'll take you about 20 minutes."
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"Why didn't you tell me that when I asked you?" asked the traveler.
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"How did I know how fast you were going to walk?" replied the old man.