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Quiznos on Craig Math Fail #fb

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I was at the Quiznos near CMU on Craig St today and noticed their 2 for $5 deal. For $5, you get to choose two items from their list of 20 items, which includes 7 salads, 5 Bullets, 4 Sammies, and 4 soups. From this menu, Quiznos says you can make over 250 combinations. But they’re wrong!

Over 250 combinations

The actual number of combinations is {20 \choose 2} + 20 = 210. {20 \choose 2} is for the number of combinations of distinct items and the final 20 is for the number of choices where you get two of the same item.

I think I know why they say 250 though. The official Quiznos menu has 23 items, for a total of 253 combinations. Quiznos franchises must source promotional material from Quiznos corporate, which prints everything up and assumes the 23 items.

This isn’t as satisfying as catching Quiznos in a fail-moment, but it serves to prove that math is useful!

Thanks to Alan and Kevin for some math help. (Alan uses pirates and gold, but I like my reasoning better.)

Written by notatypewriter

2010 April 7 at 5:49 pm

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