In this simulation, you are at the student fair in your city. Together with your friends, you have discovered that the ice cream cart is broken and you need to help repair it. However, you must first determine who, among you and your friends, is the strongest to help you out with this task. To do so, you must perform a test of strength in the game "Fair Hammer," in which you must hit with a hammer until the signal rings the upper bell. This will be completed by describing strategies for estimating natural and rational numbers. The strongest person will be able to help with repairing the ice cream cart.