Six workers build a wall in 10 days. Working at the same pace, how many days would 15 workers need?
Answer and explanation
Correct answer: B. 4 days
- Step 1: Total work = 6 x 10 = 60 worker-days. Step 2. With 15 workers: 60 / 15 = 4 days. Answer: 4 days. Why not the others: The quantities are inversely proportional; the wrong options treat them as directly proportional or subtract.
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