The Decimal System (Math Quiz)

The configuration of this abacus can be used for both decimal and hexadecimal computation
One of the oldest calculating tools still in use today is the counting frame also known as abacus: Each bead above the crosspiece is worth five units, and each bead below is worth one. The rods from right to left indicate place value in powers of ten: ones, tens, hundreds, thousands, etc. This configuration can be used for both decimal and hexadecimal computation.

If you are familiar with the rules and theory of the decimal numeral system you may skip the theory part and head down to take the math quiz and test your knowledge.


Our numeral system, also known as the decimal system, uses the figures 0, 1, 2, …, 9. The position (place) in a sequence of figures where a certain figure (digit) is listed determines its weight or value: Ones (O), Tens (D), Hundreds (H), Thousands (T), … Therefore our numeral system is also called place-value system or Decimal Numeral System. 1, 10, 100, 1000, … are the number of stages of the decimal system. They are obtained by successive multiplation with the cardinal number 10.



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