A 2-meter-long cuboid wood is sawn into 3 sections, and the surface area increases by 12 square decimeters. What is the cross-section of this cuboid wood in square decimeters
一根2米长的长方体木料，把它锯成3段，表面积增加了12平方分米，这根长方体木料的横截面是多少平方分米
<gadget id="calculator">12 / 4</gadget>
<output>3</output>

<result>3</result>