Description
Three groups of friends come to help you learn abacus. Here is the Big Friends team containing 1, 2, 3, 4, 6, 7, 8, and 9. Follow the formulas and practice the exercises. You’ll be a pro of abacus in no time. Also, don’t forget Little Friends and Mixed Friends. How to Abacus Exercise has a series of exercise books for you to sharpen your abacus and mental skills. Be sure to check them all.
