Which numbering system uses digits 0-9?

Which numbering system uses digits 0-9?

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

Answer: (D)

Numbering systems are defined by their base and the symbols used for digits. In decimal, the base is 10, so the digits available are 0 through 9, and each place represents a power of 10 (for example, 345 means 3×10^2 + 4×10^1 + 5×10^0). Other common systems use different digit sets: binary uses base 2 with digits 0 and 1; octal uses base 8 with digits 0–7; hexadecimal uses base 16 with digits 0–9 plus additional symbols (usually A–F) to represent values 10–15. Therefore, the system that uses digits 0–9 is decimal.

Numbering systems are defined by their base and the symbols used for digits. In decimal, the base is 10, so the digits available are 0 through 9, and each place represents a power of 10 (for example, 345 means 3×10^2 + 4×10^1 + 5×10^0). Other common systems use different digit sets: binary uses base 2 with digits 0 and 1; octal uses base 8 with digits 0–7; hexadecimal uses base 16 with digits 0–9 plus additional symbols (usually A–F) to represent values 10–15. Therefore, the system that uses digits 0–9 is decimal.