cuboid pool is 10 meters long, 5 meters wide, and 3 meters deep. If 7.5 cubic meters of water can be filled per hour, how many hours will it take to fill the pool with water?
一个长方体的水池，长10米，宽5米，深3米，如果每小时可以放进7.5立方米，要放满这一池水需要多少小时？
<gadget id="calculator">3 / 7.5</gadget>
<output>0.4</output>

<gadget id="calculator">10 * 5 * 0.4</gadget>
<output>20</output>

<result>20</result>