problem
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Marbles in a box
How many winning lines can you make in a three-dimensional version of noughts and crosses?
There are lots of different methods to find out what the shapes are worth - how many can you find?
A tilted square is a square with no horizontal sides. Can you devise a general instruction for the construction of a square when you are given just one of its sides?
An aluminium can contains 330 ml of cola. If the can's diameter is 6 cm what is the can's height?
Can you order the digits from 1-3 to make a number which is divisible by 3 so when the last digit is removed it becomes a 2-figure number divisible by 2, and so on?
What do you think is going to happen in this video clip? Are you surprised?