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What color was the bear?




A hunter walks one mile due south, then one mile due east, then one mile north and arrives back at his starting point. He shoots a bear. What color was it? Such a trip is possible if the hunter starts from one of the geographical poles, then circumnavigates the sides of a spherical triangle. Since there are no bears in Antarctica, the trip is assumed to have taken place in the Arctic where there are polar bears and thus the answer is "white". Versions of this problem began to appear in the 1940s. A closer examination reveals that there are many more points on the globe, other than an exact pole, from which the hunter could have begun his trek. One example is any point (of which there are an infinite number) on a circle drawn at a distance of slightly more than 1 + ½π mile from a pole – "slightly more" because of the Earth's curvature. But this is not all. The hunter could also satisfy the conditions by starting at points closer to the pole, so that the walk east would carry him exactly twice around the pole, or three times, and so on. Of course, the bear would still be white (except that polar bears don't live that far north!).


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