Which numeral system uses ten distinct symbols, 0-9?

Which numeral system uses ten distinct symbols, 0-9?

• A. Binary
• B. Hexadecimal
• C. Decimal
• D. Octal

Answer: (C)

Ten distinct symbols 0 through 9 define the decimal system, also known as base-10. In decimal, each digit represents a power of ten depending on its position, so 345 equals 3×10^2 + 4×10^1 + 5×10^0. This is the standard counting system used daily. Other numeral systems use different symbol sets: binary uses only two symbols (0 and 1) for base-2; octal uses eight symbols (0–7) for base-8; hexadecimal uses sixteen symbols (0–9 and A–F) for base-16. Therefore, the described numeral system is decimal.

Ten distinct symbols 0 through 9 define the decimal system, also known as base-10. In decimal, each digit represents a power of ten depending on its position, so 345 equals 3×10^2 + 4×10^1 + 5×10^0. This is the standard counting system used daily. Other numeral systems use different symbol sets: binary uses only two symbols (0 and 1) for base-2; octal uses eight symbols (0–7) for base-8; hexadecimal uses sixteen symbols (0–9 and A–F) for base-16. Therefore, the described numeral system is decimal.