Talk:Abacus/Manual/Quick use/Addition

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This may be a little confusing for somebody who doesn't already know how to use an abacus. Here's another way to describe it.

1+1=2:

Start with the abacus at zero:

o o o o o o
o o o o o o
| | | | | |
—----------
| | | | | |
o o o o o o
o o o o o o
o o o o o o
o o o o o o

move an earth bead in the right-hand column up for the first 1: (beads that have just been moved are shown with a *)

o o o o o o
o o o o o o
| | | | | |
—----------
| | | | | *
o o o o o |
o o o o o o
o o o o o o
o o o o o o

add the second 1 by moving up another earth bead on the right-hand column:

o o o o o o
o o o o o o
| | | | | |
—----------
| | | | | o
o o o o o *
o o o o o |
o o o o o o
o o o o o o

Now the right-hand column reads 2.

o o o o o o
o o o o o o
| | | | | |
—----------
| | | | | o
o o o o o o
o o o o o |
o o o o o o
o o o o o o

Nalberding (talk) 22:27, 25 October 2009 (UTC)[reply]