A chemical plant originally used 12.5 tons of water per day. Due to the improvement of water equipment, 20% of water can be saved every day. How many days can the original 24-day water consumption be used now?
一个化工厂原来每天用水12.5吨，由于改进用水设备，每天可节约用水20%，原来24天的用水量现在可用多少天．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">12.5 * (4/5)</gadget>
<output>10</output>

<gadget id="calculator">24 / 10</gadget>
<output>12/5 = around 2.4</output>

<gadget id="calculator">12.5 * (12/5)</gadget>
<output>30</output>

<result>30</result>