What if they had only 1p and 5p stamps?
Or 1p, 2p and 7p?
What if they didn't have 1p stamps?
How many times can you fold a piece of paper in half? Does it make any difference if the paper is large or small?
Fold or cut 16 rectangles of paper and arrange 15 as below, with a gap at the bottom right corner.
Move the X from the top left corner to the bottom right corner in as few moves as possible and devise a way to record each step for checking afterwards.
2s Factories making pairs of gloves, socks, shoes etc eg 6 pairs of shoes =12 shoes
3s Tricycle manufacture 8 tricycles=24 wheels
4s Car wheels, horseshoes, 10 horses= 40 shoes