How many square decimeters is the surface area reduced by putting together 3 cubes with sides 3 decimeters long to form a cuboid?
把3个棱长3分米的正方体拼成一个长方体，表面积减少多少平方分米
<gadget id="calculator">3 * 3</gadget>
<output>9</output>

<gadget id="calculator">9 * 4</gadget>
<output>36</output>

<result>36</result>