411 REFERENCE · Wikibooks
Using an Abacus/Subtraction
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Subtraction
Subtraction is the second most basic function of the abacus. The subract, the user displays the original number and takes away the desired amount of beads from the original number.
Example: (12-4)
12=12
000-0|-0 (1)
00-00|-0 (2)
12-4=8
0000-|-0 (0)
0-000|0- (8)
External links
Subtraction on a Japanese abacus selected from Abacus: Mystery of the Bead