The Comptometer Super Totalizer, a mechanical calculator. The Comptometer Super Totalizer, a mechanical calculator. begin-post-stats Jaap Scherphuis • 6K views end-post-stats begin-duration 11:37 end-duration Math topics: _Elementary_arithmetic_##Elementary arithmetic##_0_(number)_##0 (number)##_Addition_##Addition##_Subtraction_##Subtraction Other topics: _Mechanisms_(engineering)_##Mechanisms (engineering)##_Lever_##Lever##_Mechanical_calculator_##Mechanical calculator##_Comptometer_##Comptometer video-id: I41k4q755yE channel_Jaap_Scherphuis_ So What Learning Elementary arithmetic , Mechanisms (engineering) Monday, January 22, 2018 Share Share
