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Chocolate

There are three tables in a room with blocks of chocolate on each. Where would be the best place for each child in the class to sit if they came in one at a time?

Four Triangles Puzzle

Cut four triangles from a square as shown in the picture. How many different shapes can you make by fitting the four triangles back together?

Cut it Out

Can you dissect an equilateral triangle into 6 smaller ones? What number of smaller equilateral triangles is it NOT possible to dissect a larger equilateral triangle into?

Carrying Cards

Age 7 to 11
Challenge Level

These sixteen children are standing in four lines of four, one behind the other. They are each holding a card with a number on it.
children holding numbers
Each child in blue is holding a number which is four more than the child in the same row wearing red.
The children in yellow shirts each have a number which is double the number of the child in the same row wearing red.
Some of the numbers that the children in red, blue or yellow shirts are holding have got rubbed off. What should the numbers be?
Can you work out how the numbers that the children in green are holding have been worked out? What are the two missing numbers?
If there was another row of four children standing behind the fourth row, what numbers would they be holding?

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