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On the planet Vuv there are two sorts of creatures. The Zios have 3 legs and the Zepts have 7 legs. The great planetary explorer Nico counted 52 legs. How many Zios and how many Zepts were there?

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You have two sets of the digits 0-9. Can you arrange these in the five boxes to make four-digit numbers as close to the target numbers as possible?

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What can you say about these shapes? This problem challenges you to create shapes with different areas and perimeters.

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Can you use the information to find out which cards I have used?

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Kate has eight multilink cubes. She has two red ones, two yellow, two green and two blue. She wants to fit them together to make a cube so that each colour shows on each face just once.

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The discs for this game are kept in a flat square box with a square hole for each. Use the information to find out how many discs of each colour there are in the box.

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Can you make a cycle of pairs that add to make a square number using all the numbers in the box below, once and once only?

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In this game for two players, take it in turns to shade one petal, or two petals next to each other. Is it better to go first or second?

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Can you see how these factor-multiple chains work? Find the chain which contains the smallest possible numbers. How about the largest possible numbers?