Which base uses digits 0-7?

Which base uses digits 0-7?

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

Answer: (B)

Octal is the numeral base that uses digits 0 through 7. In a base-8 system, each place value represents eight times the value of the place to its right, and there are eight distinct digits available: 0, 1, 2, 3, 4, 5, 6, and 7. This is why any number written in octal uses only those digits. Why this fits here: the question asks for the base that uses exactly the digits 0 through 7, which is the defining feature of octal. In contrast, decimal uses digits 0–9, binary uses digits 0–1, and hexadecimal uses digits 0–9 plus A–F (representing 10–15), so none of them are limited to 0–7.

Octal is the numeral base that uses digits 0 through 7. In a base-8 system, each place value represents eight times the value of the place to its right, and there are eight distinct digits available: 0, 1, 2, 3, 4, 5, 6, and 7. This is why any number written in octal uses only those digits.

Why this fits here: the question asks for the base that uses exactly the digits 0 through 7, which is the defining feature of octal.

In contrast, decimal uses digits 0–9, binary uses digits 0–1, and hexadecimal uses digits 0–9 plus A–F (representing 10–15), so none of them are limited to 0–7.