A Level Computer Science OCR Practice Exam

Which of the following best describes the denary numerical system?

1. Uses 16 as its base

2. Uses 10 as its base

3. Uses 8 as its base

4. Uses 2 as its base

The correct answer is: Uses 10 as its base

The denary numerical system, also known as the decimal system, is based on ten distinct digits, ranging from 0 to 9. This base-10 system is the one most commonly used in everyday life for counting and arithmetic. Each place value in a denary number represents a power of 10, with the rightmost digit representing \(10^0\) (which is 1), the next one \(10^1\) (which is 10), followed by \(10^2\) (which is 100), and so on. The other options represent different numerical systems: the base-16 system, or hexadecimal, which uses sixteen distinct symbols; the base-8 system, or octal, which uses eight symbols; and the base-2 system, or binary, which uses only two symbols (0 and 1). These systems serve specific purposes, especially in computing, but they do not define the denary system. Thus, the correct answer is indeed that the denary numerical system uses 10 as its base.