It is an illusion for acrobatic troupe dogs to learn arithmetic. In fact, the actor is doing arithmetic, just directing the dog to act. The dog in the acrobatic troupe is not born to "do" arithmetic, and the actor needs some training to train it to do arithmetic. During training, the actor uses a certain action to instruct the dog to hold various gestures with arithmetic answers, and each gesture is represented by one action.

In this way, after long-term training, although the puppy doesn't "know" the words on the sign, he is deeply impressed by the actor's every move, and can obey the actor's command and hold the sign with the answers to arithmetic problems written on it.

The source of acrobatics:

Around the Neolithic Age, acrobatics had sprouted in China. The labor skills formed by primitive people in hunting, martial arts and extraordinary physical ability created in self-defense and attack and defense, as a skill performance reproduction of self-entertainment games during rest and entertainment, formed the earliest acrobatic art. Acrobatics scholars believe that the earliest acrobatic program in China is Flying Man.

This is a cross-shaped hunting equipment made of hardwood fragments. Hunters of primitive tribes often use this rotating weapon to attack birds and animals. In the process of continuous throwing, they found that different crosses can "come and go" under the action of the wind, so they became the programs performed in the clan meeting of primitive tribes.