3 machines produce 120 items in 8 minutes. At the same rate, how many items would 9 machines produce in 16 minutes?
Answer and explanation
Correct answer: A. 720
- Step 1: Output is proportional to both the number of machines and the time.
- Step 2: New output = 120 × rac{9}{3} × rac{16}{8} = 720.
Answer
720.
Why not the others: 360: the change in time is ignored. 240: the change in the number of machines is ignored. 80: the machine ratio is inverted.
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