Nim-7 game for an adult and child. Who will be the one to take the last counter?
What is the greatest number of counters you can place on the grid below without four of them lying at the corners of a square?
Can you visualise what shape this piece of paper will make when it is folded?
Can you arrange the digits 1, 1, 2, 2, 3 and 3 to make a Number Sandwich?