Can you set the logic gates so that this machine can decide how many bulbs have been switched on?
Use cunning to work out a strategy to win this game.
Try to solve this very difficult problem and then study our two suggested solutions. How would you use your knowledge to try to solve variants on the original problem?
Can you crack these very difficult challenge ciphers? How might you systematise the cracking of unknown ciphers?
The clues for this Sudoku are the product of the numbers in adjacent squares.
How can you quickly sort a suit of cards in order from Ace to King?