An ancient castle located at the foot of the mountain may collapse, and ordinary bats have become the reason for this. The whole population living in caves nearby decided to move to the castle, and its owners do not like it at all. To do this, use a special mathematical gun. The mice will appear on top, and above them you will see an example. Quickly solve it and write the answer on the panel below, and then click on the gun to shoot. In the case of the correct answer, the shot will reach the goal.