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Three Squares

What is the greatest number of squares you can make by overlapping three squares?

Two Dice

Find all the numbers that can be made by adding the dots on two dice.

Biscuit Decorations

Andrew decorated 20 biscuits to take to a party. He lined them up and put icing on every second biscuit and different decorations on other biscuits. How many biscuits weren't decorated?

Domino Sorting

Age 5 to 7
Challenge Level

Here are some dominoes taken out of the full set:
dominoes from 1, 0 to 3, 3

Sort them into two groups - one group with an odd number of spots and one group with an even number of spots.
Do you have any dominoes left over? Why or why not?

Now put the dominoes into pairs. The number of spots on each pair of dominoes must make a total of $5$.
How many pairs can you make?
Which dominoes are left over?

Can you pair them up in any different ways so that each pair adds to $5$?
Which dominoes are left over now?

Are there any dominoes which are always left over?
Can you explain why?

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.
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