Difficulty: Easy
Correct Answer: Q3/P2 units
Explanation:
Introduction / Context:This algebraic work-rate problem asks you to deduce per man-hour productivity from one scenario and then apply it to another. It tests understanding that total work equals (men) * (hours/day) * (days) * (productivity per man-hour).
Given Data / Assumptions:
Concept / Approach:From the P-scenario, compute productivity k (units per man-hour). Then compute work for the Q-scenario using the same k. Finally, simplify the expression purely in terms of P and Q to match an option.
Step-by-Step Solution:
P men * P h/day * P days * k = P units⇒ P^3 * k = P ⇒ k = 1 / P^2For Q men: Work = Q men * Q h/day * Q days * k = Q^3 * (1/P^2) = Q^3 / P^2Verification / Alternative check:Dimensional check: if P = Q, expression gives P^3/P^2 = P, consistent with the original statement; hence the form is correct.
Why Other Options Are Wrong:
Common Pitfalls:Assuming work is simply proportional to men*hours*days without factoring in k from the first scenario, or mis-simplifying exponents. Keep the per man-hour productivity explicit.
Final Answer:Q3/P2 units
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