ISBN: 9787565032943 - 儿童珠心算简易教学法(上) (1 risultati)

paperback. Condizione: New. Paperback. Pub Date: 2017-02-01 Pages: 125 Language: Chinese Publisher: Hefei University Press abacus. abacus is a type of short mental arithmetic. also known as Pearl brain speed calculation. it is the digital counting beads become symbols come human mind. and a style of computing abacus arithmetic operations based on the principle that it is not only fast computing capabilities .…