The sum of the lengths of all the edges of a cuboid is 36 cm, what is the sum of the lengths of the three edges intersecting at a certain vertex in cm.
一个长方体的所有棱长之和是36cm，相交于某一个顶点三条棱长之和是多少cm．
<gadget id="calculator">36 / 4</gadget>
<output>9</output>

<result>9</result>