It is possible to develop all mathematical theorems (laws) from a set of assumptions called axioms or postulates.
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"Octo" is a prefix meaning "eight". An Octopus has eight legs. An octagon has exactly 8 sides. An Octogenarian is at least 8 decades old. What is the eighth month?

How many people must be in a room so that you are sure that at least two must have the same birthdate?
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