Try ancient calculation systems
Solve the same multiplication in four notation systems and feel why Hindu-Arabic numerals changed the world.
A question to carry first
Are numerals marks for answers, or tools that move a calculation?
The same multiplication exposes different steps and different places for error when its notation and tool change. Before timing yourself, notice what makes your hand stop.
Current calculation world
Mediterranean recording practices
Values are visible, but the intermediate steps of multiplication are hard to unfold in the notation alone.
These traditions are not a single line of progress. They developed for different recording, trade, teaching, and astronomical settings across time and place.
💡 Roman numerals have no place value, which makes multiplication extremely difficult. Try it with pencil and paper—the difficulty is intentional.