I count across and then down, but otherwise this same method. What's great is that it tallies up to 144, with both hands. You can also do some basic math operations, but they're limited and no faster than doing it in your head - certainly not anything near as useful as the hand abacus method.
I count across and then down, but otherwise this same method. What's great is that it tallies up to 144, with both hands. You can also do some basic math operations, but they're limited and no faster than doing it in your head - certainly not anything near as useful as the hand abacus method.