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in reply to Re^3: Spooky math problem
in thread Spooky math problem

It is possible to do it by choosing a number before you see the one in the envelope.

But it is also possible to do it by choosing a number through a mechanical procedure (eg a series of coin flips), in which case it doesn't matter whether you see the number in the envelope first.

However you're exactly right that the method of choosing the random number cannot depend on the number that you see.