ok guys try this one........
3 lads walking past Comets and they see a radio in the window for £30 that they like the look of and decide to buy.
they approach the salesman and say, we'd like to buy that radio for £30 please, and each lad hads over £10.....3 x £10 = £30
the salesman comes back with the radio and says...lads, it's your lucky day, the radio is in the sale, it's £25.
the salesman has the change, 5 x £1 coins in his hand and says.....here's £1 back to each of you and because i told you about the sale, i'm going to keep the last £2.
So.....if each lad handed over £10 and got £1 change, they each spent £9......3 x £9 = £27 and the £2 that the salesman kept = £29.....
where did the other pound go ?