Keywords: abacus hat beads addition add sum computation indoor I'm now adding 7 in the 7th position from the left. This is done in 3 steps: add 10, subtract 5, add 2. In this step I subtract 5. CC0 waiver: To the extent possible under law, I waive all copyright and related or neighboring rights to this work. I'm now adding 7 in the 7th position from the left. This is done in 3 steps: add 10, subtract 5, add 2. In this step I subtract 5. CC0 waiver: To the extent possible under law, I waive all copyright and related or neighboring rights to this work. |