MATHINFINITY

ZHUSUAN AND ABACUS

Zhusuan is a method of mathematical calculation using abacus. It was inscribed on the representative list of the intangible cultural heritage of humanity by UNESCO in 2013. In the days when there were no calculators or computer, abacus was a very useful tool for performing addition, subtraction, multiplication, division and even more complication calculations.

Different types of abacus have different fingerings and formulas. The most common type of abacus has seven beads per rod. On each rod, the beads are separated by the beam, making it two in the upper deck and five in the lower deck. Each bead in the upper deck equals five, those in the lower deck equals one. Normally, people only use their thumbs, forefingers and middle fingers to operate the abacus.

Did you know?

  1. Do you want to know if it is faster to use the abacus or calculator to do additions?
  2. Get an abacus and a piece of paper. Calculate 13,079.6 + 671.3 according to the Oral Formulas of Zhusuan and write down the answer in Huama.