In a floating-point system, what does the exponent do?

• A. Defines the sign
• B. Plays with scale by powers of base
• C. Stores metadata only
• D. Sets precision

Answer: (B)

In floating-point numbers, the exponent controls scale. The value is basically the significand multiplied by the base raised to the exponent, so the exponent moves the decimal (or binary) point to make numbers much larger or smaller. In binary systems, that means multiplying by powers of two to represent huge magnitudes or tiny fractions without needing more digits in the significand. The sign bit determines whether the number is negative, while precision comes from how many bits the significand has, not from the exponent. The exponent is typically stored with a bias to allow negative exponents, enabling a wide range of magnitudes. For example, 1.625 × 2^3 is 13, and 1.0 × 2^-10 is about 0.0009766.