The number of spots in a deck is 365?

Marco Tempest

Marco Tempest

Today’s TED video is an augmented reality card trick by Marco Tempest. Now, I’m a fan of card tricks but this was a bit too cutesy for me. However, I draw your attention to his computer’s claim (at 3:20) that if you add up all the spots on the cards in a deck then you get 365 which is the number of days in a year. I make the same claim in one of my school talks but I follow it by pointing out that obviously it can’t be right. (Obvious in the sense that you don’t need to get a deck and count but just use some simple maths.) Usually at least one of the pupils gets it.

Anyhow, here’s the video:

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