• Published 19th Sep 2018
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Life is a Test: A Series of Pony Logic Puzzles - Brony_of_Brody



The Mane 6 and Friends face a perplexing pile of pony puzzles. Probably.

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The Answer 17

Rainbow Dash has a 50% chance of sitting in her seat.

To explain, let's simplify things. Suppose Old Oak and Rainbow Dash were the only passengers and there were only two seats. If Old Oak chooses to sit in a random one, there's a 50:50 chance Rainbow'll get her seat. No duh.

What if we introduced another passenger? Well, assuming Old Oak randomly sits in the seat of this third passenger, they are forced to choose between either Old Oak's seat, or Rainbow Dash's. As we're only considering 'the odds that Rainbow Dash will get her seat', this is still a 50% chance Rainbow will have to sit in Old Oak's unclaimed seat.

Using recursive logic, we know that in the case of 500 passengers, the odds are, surprisingly, exactly the same. Old Oak randomly sitting anywhere else only postpones the decision: it doesn't affect the odds at all!

Still confused? Say Old Oak randomly sits in seat 212. Passengers 2 to 211 will sit in their correct seats. Now it comes to the 212th passenger, and one of three things could happen:

  1. They randomly sit in Old Oak's seat.
  2. They randomly sit in Rainbow Dash's seat.
  3. They randomly sit elsewhere and the decision is postponed still further.

Let's say this random passenger sits in seat 479. Now we continue on with all passengers sitting in their correct seats until the 479th passenger lines up and does one of the three actions.

Assuming nopony randomly sits in Old Oak's seat or Rainbow's, this pattern will repeat for all passengers until passenger 499 is stuck with picking either Old Oak's unclaimed seat, or Rainbow's.

Rainbow Dash can ONLY sit in Old Oak's seat, or hers. There is no other possible outcome. This is like tossing a coin: you can put off the coin flip, but not forever. You'll have to face the 50:50 odds sooner or later!

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