Work measurement: Time study aims to determine the job time required by which level of worker performance?

Introduction / Context:
Classical time study seeks a fair and attainable standard time. It removes individual pace bias by rating performance and applying allowances so the standard reflects an average qualified worker under normal conditions.

Given Data / Assumptions:

• Observer records cycle times for a qualified worker.
• A performance rating system (e.g., 100% = normal) is used.
• Allowances account for personal needs, fatigue, and delays.

Concept / Approach:
Standard time = Normal time * (1 + Allowance). Normal time = Observed time * Rating factor. The target is the time an average trained worker would need at normal pace, not the extremes of speed or slowness.

Step-by-Step Solution:

Verification / Alternative check:
Compare with predetermined motion time systems (e.g., MTM); both target average capable performance rather than best or worst cases.

Why Other Options Are Wrong:
Slow or fast workers distort fairness; apprentices may lack competence, so their times are not representative.

Common Pitfalls:
Over- or under-rating performance; neglecting allowances; setting standards on unstable methods.

Final Answer:
An average (qualified) worker at a defined performance rating