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## 'Card Game (a Simple Version of Clock Patience)' printed from http://nrich.maths.org/

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### Rules

Four cards (two cards with 1 and two with 2) are shuffled and
placed into two piles of two

You have two trays labelled 1 and 2.

Starting with the first pile of cards - turn a card over:

- If the card has a 1 on it - place it in tray 1 and take a card
from pile 1
- If the card has a 2 on it - place it in tray 2 and turn over
the next card in pile 2.

You **win** if all your cards end up in the trays
before you run out of cards in one pile.

You **lose** if there are cards left in a pile that
you cannot reach.

What is the probability that you win?

What happens if you have six cards in the two piles (three with
one and three with 2)?

Do your odds increase or decrease?

Can you see any patterns in successful and unsuccessful
placement of cards in the piles?