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In how many different positions can the two blue marbles settle?
How many of these positions contain the two marbles touching?

These Recording Sheets might be useful for finding all possible combinations.
 

 

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Six balls are shaken. You win if at least one red ball ends in a corner. What is the probability of winning?

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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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