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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?

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Zios and Zepts

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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Fractions in a Box

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

Light the Lights Again

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

This problem is similar to Light the Lights, but slightly more tricky. You may like to try that one first.


Here is a machine with four coloured lights. Each light responds to a rule.

When you type in a number, lights go on if their rule is satisfied.
If the number satisfies more than one rule, then more than one colour will light up.

Type in some numbers and see which lights you can switch on.







What is the smallest number which lights up all the lights?