A cube fuel tank with a side length of 6 decimeters is filled with diesel oil. If this tank of diesel oil is poured into another rectangular parallelepiped fuel tank with a length of 9 decimeters and a width of 6 decimeters, how deep is the diesel tank?
一个正方体油箱，棱长6分米，里面装满柴油，如果把这箱柴油全部倒入另一个长9分米，宽6分米的长方体空油箱里，那么柴油箱深多少分米？
<gadget id="calculator">6 * 6 * 6</gadget>
<output>216</output>

<gadget id="calculator">9 * 6</gadget>
<output>54</output>

<gadget id="calculator">216 / 54</gadget>
<output>4</output>

<result>4</result>