There is a cuboid container with a length of 5 decimeters, a width of 4 decimeters, and a height of 6 decimeters. Water is poured into it, and the water depth is 3.5 decimeters. If a cube of iron 3 decimeters long is immersed in water, how many decimeters will 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，里面注入水，水深3.5分米．如果把一块长3分米的正方体铁块浸入水中，水面上升了多少分米？
<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<gadget id="calculator">3 / 20</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">3 * 3 * (3/20)</gadget>
<output>27/20 = around 1.35</output>

<result>27/20 = around 1.35</result>