cube fish tank without a cover has a side length of 0.4 meters measured from the inside. Use a pot with a volume of 5 liters to add water to it. After filling eight pots of water, how deep is the fish tank now?
一个无盖的正方体鱼缸，从里面量棱长是0.4米，用容积是5升的壶往里加水，加了满满八壶水后，鱼缸现在水深多少米？
<gadget id="calculator">0.4 * 10 * 0.4 * 10</gadget>
<output>16</output>

<gadget id="calculator">8 / 16 / 10</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">5 * (1/20)</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>