There is a cuboid container with a length of 5 decimeters, a width of 4 decimeters and a height of 6 decimeters measured from the inside. Water is filled inside and the depth of the water is 3 decimeters. How much did the water level rise?
有一个长方体容器，从里面量长5分米，宽4分米，高6分米，里面注有水，水深3分米，如果把一棱长2分米的正方体铁块完全浸没在水中，水面上升多少？
<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<gadget id="calculator">2 / 20</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">2 * 2 * (1/10)</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>