Exam-style question
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A system must choose between a fixed-point format and a floating-point format. Explain how allocating more bits to the fractional part of a fixed-point value affects its range and precision, and then explain why floating point may be selected instead.
Model answer
What a good answer should say
- In a fixed-point format, the binary point remains in the same position.
- If more bits are allocated to the fractional part, the system can represent fractional values with greater precision.
- However, fewer bits remain for the whole-number part, so the range of whole-number values becomes smaller.
- Floating point may be selected when the system needs to represent a wider range of values.
Explanation
Why this works
The answer links the allocation of bits directly to the trade-off between precision and range. It also explains a reason for choosing floating point while acknowledging its possible disadvantages.
Common mistake
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