Five workers can build a wall in 12 days, all working at the same rate. How many days would 8 workers need for the same wall?
Answer and explanation
Correct answer: D. 7.5 days (60 worker-days shared by 8 workers)
- Step 1: Total work = worker-days. Step 2. With 8 workers: days. Answer: 7.5 days. Why not the others: More workers means fewer days (inverse proportion), so 19.2 days is wrong; 4.5 and 9 use subtraction, not proportion.
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