Keywords: abacus hat beads addition add sum computation indoor I'm now adding 7 in the hundreds position. This is done in 2 steps: add 10, subtract 3. In this step I add 10 by adding 1 in the thousands position. 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 hundreds position. This is done in 2 steps: add 10, subtract 3. In this step I add 10 by adding 1 in the thousands position. CC0 waiver: To the extent possible under law, I waive all copyright and related or neighboring rights to this work. |