A cuboid is exactly divided into three cubes of equal shape and size, so that the increased surface area is equal to the surface area of the original cuboid.
一个长方体正好分割成3个形状、大小相等的正方体，这样增加的表面积相当于原长方体表面积的多少．
<gadget id="calculator">4 / 14</gadget>
<output>2/7 = around 0.285714</output>

<result>2/7 = around 0.285714</result>