3 machines produce 360 items in 12 minutes. At the same rate, how many items would 9 machines produce in 6 minutes?
Answer and explanation
Correct answer: B. 540
- Step 1: Output is proportional to both the number of machines and the time.
- Step 2: New output = 360 × rac{9}{3} × rac{6}{12} = 540.
Answer
540.
Why not the others: 1080: the change in time is ignored. 180: the change in the number of machines is ignored. 60: the machine ratio is inverted.
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