A cube container with side length 3 decimeters contains (3/5) water. Now a stone is submerged in water, the water level rises to 2.5 decimeters. What is the volume of this stone in cubic decimeters?
一个棱长为3分米的正方体容器，里面盛有(3/5)的水．现在把一个石头浸没在水中，水面上升到2.5分米．这个石头的体积是多少立方分米？
<gadget id="calculator">3 * 3 * 2.5</gadget>
<output>22.5</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">3 * 3 * 3 * (3/5)</gadget>
<output>81/5 = around 16.2</output>

<gadget id="calculator">22.5 - (81/5)</gadget>
<output>6.3</output>

<result>6.3</result>