3 sets of rice milling machines mill 4860 kg of rice in 4.5 hours. How many hours does it take to grind 10,800 kilograms of rice with one such rice mill?
3台碾米机4.5小时碾米4860千克．用一台这样的碾米机要碾米10800千克，需要多少小时？
<gadget id="calculator">4_860 / 4.5 / 3</gadget>
<output>360</output>

<gadget id="calculator">10_800 / 360</gadget>
<output>30</output>

<result>30</result>