From: MagisbIadius | #018A group has two people. A person has 1/60 chance to post in a minute*. The second person has a (1/60) * (1/60) = 0.03% chance to post in the same minute.

If both person A and person B are guaranteed to post during minute X, then out of the 3600 permutations of seconds, there are 60 in which person A's second and person B's second are the same. Thus, the odds are 1/60.

Of course, that's not really a useful statistic. You have to look at board activity, and if the question is something that is easily answered. The majority of same times posts I've seen or had have been two people answering the same question with the same short answer. The strike zone there is pretty wide, but basically you want to look at when you expect someone to respond, the odds of someone responding just as quickly, and how many seconds apart you expect the responses could reasonably be. Though really, that's just ballparking, and the odds are pretty loose no matter how you try to calculate it.

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