Bert has a game at a fair. In the game the players pay to spin a wheel. When the wheel stops, the amount shown by the arrow is given to the player. Here are the probabilities that the wheel will stop on 5p, 10p, 20p and 50p.
5p = 0.5
10p = 0.25
20p = 0.15
50p = 0.1
Bert wants to make a profit from the game. Work out the minimum he can charge players to spin the wheel.