A neat coincidence happened as our local pinball league got plans under way for tonight. There are thirteen pinball machines in the local venue, and normally four of them get picked for the night’s competition. The league president’s gone to a randoom number generator to pick the machines, since this way he doesn’t have to take off his hat and draw pinball table names from it. This week, though, he reported that the random number generator had picked the same four tables as it had last session.

There’s a decent little probability quiz to be built around that fact: how many ways there are to get four tables out of the thirteen available, obviously, and from that what the chance is of repeating the selection of tables from the last session. And there are subtler ones, like, what’s the chance of the same tables being drawn two weeks in a row over the course of the season (which is eight meetings long, and one postseason tournament), or what’s the chance of any week’s selection of tables being repeated over the course of a season, or of a year (which has two seasons). And I leave some space below for people who want to work out these problems or figure out similar related ones.

It’s also a reminder that just because something is randomly drawn doesn’t mean that coincidences and patterns won’t appear. It would be a touch suspicious, in fact, if the random number generator never picked the same table (or several tables) in successive weeks. But it’s still a rare enough event that it’s interesting to see it happen.

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## Author: Joseph Nebus

I was born 198 years to the day after Johnny Appleseed. The differences between us do not end there. He/him.
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Coincidences make life more exciting after all…

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They make life exciting and also charmingly personal, somehow. They add intimacy to events.

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As Stéphane Mallarmé would say: “Un coup de dés jamais n’abolira le hasard” : “(Random) dice rolling will not abolish Fate”… Great post Joseph! :star: Best wishes, Aquileana :D

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Thank you. And that’s a good quote.

The most wondrous thing to me is that it seems like dice-rolling

isfate, at least in certain contexts. It’s amazing to see that work.LikeLiked by 1 person

Good day! I hope you have remedied your eating of carrot cake?

In any case I have sent a well deserved Award your way my friend.

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You know, I haven’t got to the carrot cake yet, but I did have a doughnut today. And thanks kindly for the nomination.

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Well, I suppose a doughnut will do as it’s still a nice sweet treat to be having after all. :)

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It so is. I should get one as we head out today, come to think of it.

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Yes indeed you should. Top priority possibly..

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