You can do subtraction on these too but it’s super confusing (to me at least)
Multiplication should work the same as the comptometer though! It’s pretty much fast addition with some math tricks but it makes these sorts of adding machines super useful still
I'm not really sure. Now that I think about it, maybe multiplication is only working through repetitively turning the crank. Have to dig it out in the basement and test it again. 😬
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You can do subtraction on these too but it’s super confusing (to me at least)
Multiplication should work the same as the comptometer though! It’s pretty much fast addition with some math tricks but it makes these sorts of adding machines super useful still