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Plum Tree

Label this plum tree graph to make it totally magic!

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Magic W

Find all the ways of placing the numbers 1 to 9 on a W shape, with 3 numbers on each leg, so that each set of 3 numbers has the same total.

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2-digit Square

A 2-Digit number is squared. When this 2-digit number is reversed and squared, the difference between the squares is also a square. What is the 2-digit number?

Triangles Within Triangles

Age 14 to 16 Challenge Level:

Why not encourage pupils to discover rules of their own?

By using isometric paper the triangular numbers can be represented as equilateral triangles wich give scope to investigating their connection with hexagonal numbers.

This problem links to "Triangles within Squares ".