There is a rectangular reservoir with a length of 80 decimeters, a width of 7 meters and a height of 3 meters. If 3,000 liters of water are stored in the pool and 1,000 liters of water are released every hour, how many hours does it take for the pool to be filled?
有一个长方形蓄水池，长80分米，宽7米，高3米．如果每小时向水池蓄水3000升，放出1000升水，那么这个水池多少小时才能蓄满？
<gadget id="calculator">7 * 10</gadget>
<output>70</output>

<gadget id="calculator">3 * 10</gadget>
<output>30</output>

<gadget id="calculator">80 * 70 * 30</gadget>
<output>168_000</output>

<gadget id="calculator">3_000 - 1_000</gadget>
<output>2_000</output>

<gadget id="calculator">168_000 / 2_000</gadget>
<output>84</output>

<result>84</result>