The complete formula of one up one two up two three down five go two is one up one, two up two, three down five divided by two, four down five divided by one, five go five go into one, six up one Go five to one, seven to two, five to one, eight to two, nine to one and one, fight three times, and in the last step, one retreats and one returns one.

The abacus is a form of manually operated calculation aid. It originated in China and has a history of more than 2,600 years. It is an important invention in ancient China. Before the advent of Arabic numerals, the abacus was a widely used calculation tool around the world. Today, the abacus continues to be used in parts of Asia and the Middle East, especially in shops, where it can be purchased from stores that offer Chinese and Japanese goods.

In the West, it is sometimes used to help young children understand numbers, and some mathematicians like to experience using an abacus to solve simple arithmetic problems.

Explanation of related content

Abacus, also known as abacus, is a simple calculation tool invented by our ancestors. Abacus originated in the Northern Song Dynasty. beads. The abacus is a simple calculation tool invented by the working people of ancient China. China is the hometown of the abacus. Today, when computers are widely used, the ancient abacus has not been abandoned. Instead, it is in the ascendant in many countries because of its flexibility, accuracy and other advantages.

Therefore, people often compare the invention of the abacus with the four great inventions of ancient China. In the famous painting "Along the River During the Qingming Festival" in the Northern Song Dynasty, there is an abacus in the medicine shop cabinet of Zhao Taicheng's family. Because of the convenience and speed of abacus calculations, it has been a commonly used calculation tool by the working people of ancient China for thousands of years. Even the most advanced electronic calculators in modern times cannot completely replace the role of abacus.