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

**INTRODUCTION:**

The cardinal number (or base) of the binary numeral system is the figure “2”. Thus only 2 figures are necessary to express numbers by this binary system: typically 0 and 1. Such numbers represented in this system are therefore commonly called binary numbers. The locic gates in the digital electronic circuits of modern-day computers and mobile phones and their software are based on the binary numeral system, which explains the importance of this numeral systems.

**EXAMPLE** for the conversion of the binary number 100101 to the decimal numeral system:

- 101001
_{2}= [ (**1**) × 2^{5}] + [ (**0**) × 2^{4}] + [ (**1**) × 2^{3}] + [ (**0**) × 2^{2}] + [ (**0**) × 2^{1}] + [ (**1**) × 2^{0}]

- = [
**1**× 32 ] + [**0**× 16 ] + [**1**× 8 ] + [**0**× 4 ] + [**0**× 2 ] + [**1**× 1 ]

**= 41**_{10}

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