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For younger learners

  • Early Years Foundation Stage

Flippin' Discs

Age 11 to 14
Challenge Level Yellow star
Secondary curriculum
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources


Flippin' Discs printable sheet


Imagine you have two discs. Each disc is red on one side and green on the other.

You flip the discs, and when they land, you win if both discs show the same colour.



Click "Run Once" to complete a throw. Did you win?
Click a few more times and look at your results after several throws.

Approximately how often do you think you would win if you completed $100$ throws?
Make a prediction and then check it by doing the experiment.

Now click on the purple cog in the top right corner and change the number of discs to $3$. You win if all the discs show the same colour.

Can you predict what the probability of winning will be this time?
Check that your prediction matches the results from the interactivity.

Do the same with $4$ and $5$ discs.

Do you notice a pattern in your results? Can you explain it?

 

Can you explain how to find the probability of winning for $n$ discs?

 

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All you need for this game is a pack of cards. While you play the game, think about strategies that will increase your chances of winning.

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This is a game for two players. Does it matter where the target is put? Is there a good strategy for winning?

Game of PIG - Sixes

Can you beat Piggy in this simple dice game? Can you figure out Piggy's strategy, and is there a better one?

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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