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Rotating Triangle

What happens to the perimeter of triangle ABC as the two smaller circles change size and roll around inside the bigger circle?

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Draw a 'doodle' - a closed intersecting curve drawn without taking pencil from paper. What can you prove about the intersections?

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Russian Cubes

I want some cubes painted with three blue faces and three red faces. How many different cubes can be painted like that?

Iffy Logic

Stage: 4 and 5 Challenge Level: Challenge Level:1

Some cards can make multiple answers. See if you can first use the cards which have an obvious partner to start to eliminate some of the possibilities.