How many different colours of paint would be needed to paint these
pictures by numbers?
This game challenges you to locate hidden triangles in The White
Box by firing rays and observing where the rays exit the Box.
Which of these triangular jigsaws are impossible to finish?
This problem is a sequence of linked mini-challenges leading up to the proof of a difficult final challenge, encouraging you to think mathematically. Starting with one of the mini-challenges, how many of the other mini-challenges will you invent for yourself?
Take three whole numbers. The differences between them give you
three new numbers. Find the differences between the new numbers and
keep repeating this. What happens?