Time study fact-check: “Normal time is the ratio of representative time to the rating factor.” Is this statement correct?
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ATrue
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BFalse
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CTrue only when rating > 1
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DTrue only for synthetic data systems
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ETrue only with zero allowances
Answer
Correct Answer: False
Explanation
Introduction / Context:Normal time links observed performance to a standard pace. Getting the formula right is critical for calculating standard times and fair incentives.
Given Data / Assumptions:
- Representative (observed) time = average measured cycle time.
- Rating factor R expresses performance relative to normal (e.g., 1.10 for 110%).
- Allowances are not part of normal time; they are added later.
Concept / Approach:The correct relationship is: Normal time = Representative time * Rating factor. The statement claims a ratio (division), which is incorrect. Using division would penalize higher ratings by reducing normal time wrongly and misstate standards.
Step-by-Step Solution:
Compute representative time from multiple cycles.Apply rating: Normal time = Rep time * R.Compute standard time: Standard time = Normal time / (1 − allowance fraction).Verification / Alternative check:Example: Rep time 1.0 min, R = 1.2. Correct Normal time = 1.2 min. Dividing would give 0.833 min, which contradicts the idea that faster-than-normal performance implies more time at normal pace.
Why Other Options Are Wrong:Qualifiers in (c), (d), and (e) do not fix the algebra; the relation is multiplication regardless of R or allowances.
Common Pitfalls:Mixing up rating factor with performance percentage; forgetting to separate allowances from the normal time stage.
Final Answer:False