In the market near Quiz Master Shop Towers there are two stallholders who sell peaches, and very nice peaches they are too.
The first stallholder sells small peaches at three for £1. He sells 30 peaches every day which, of course, brings in £10.
The second stallholder sells big peaches at two for £1. He also sells 30 peaches every day which, of course, brings in £15.
One day recently one of the stallholders was otherwise occupied. In an act of kindness the other stallholder took his stock of 30 peaches for the day and sold peaches of both sizes. As before it was three small peaches or two big peaches for £1.
In order to move the peaches more quickly, because he did have twice as many as normal to sell, he decided to sell five peaches for £2. This did indeed work, and peaches flew off the stall.
When he added up the takings he found he had £24. But £15 and £10 total £25, so where is the missing pound?
Well, the problem with selling five peaches (two big and three small) for £2 is that you exhaust your stock of small peaches before the big ones.
After selling ten bundles for £20 all the small peaches are gone but ten large peaches remain. Selling these at five for £2 brings in £4, making the £24 total.