A cuboid container with a length of 5 cm, a width of 4 cm, and a height of 20 cm contains water. If an iron block with a volume of 100 cubic centimeters is immersed in it, the height of the water surface will be 18 cm. How many liters of water were there originally in the container?
一个长是5厘米，宽是4厘米，高是20厘米的长方体容器中装有水，如果把一个体积为100立方厘米的铁块浸没在其中，这时水面高度为18厘米．容器中原来有水多少升？
<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<gadget id="calculator">100 / 20</gadget>
<output>5</output>

<gadget id="calculator">18 - 5</gadget>
<output>13</output>

<gadget id="calculator">13 / 1_000</gadget>
<output>13/1_000 = around 0.013</output>

<gadget id="calculator">5 * 4 * (13/1_000)</gadget>
<output>13/50 = around 0.26</output>

<result>13/50 = around 0.26</result>