Put two identical cubes together to form a cuboid. The surface area of the cuboid is 40 square centimeters. Find the surface area of a cube.
把两个相同的正方体拼成一个长方体，长方体的表面积是40平方厘米，求一个正方体的表面积．
<gadget id="calculator">40 / 10</gadget>
<output>4</output>

<gadget id="calculator">4 * 6</gadget>
<output>24</output>

<result>24</result>