Please do NOT post your answers, but do say if you think you have solved the puzzles and how long it took. Solution on Monday.
John weights much more than 20 stone. He goes to the shops to buy some scales, but the scales there only go up to 20 stone. However, he comes up with a way of accurately weighing himself every day using the scales. What was his plan?
I have produced an ebook containing 101 of the previous Friday Puzzles! It is called PUZZLED and is available for the Kindle(UKhere and USA here) and on the iBookstore (UK here in the USA here). You can try 101 of the puzzles for free here.