A cylindrical tin bucket without a cover is 15 decimeters high, and the diameter of the bottom surface is high (3/5). How many square decimeters of tin should be used to make this bucket?
一个无盖的圆柱形铁皮水桶，高为15分米，底面直径是高的(3/5)，做这个水桶，至少用铁皮多少平方分米？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">15 * (3/5)</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9 * 15</gadget>
<output>423.9</output>

<gadget id="calculator">(3/5) / 2</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">15 * (3/10)</gadget>
<output>9/2 = around 4.5</output>

<gadget id="calculator">(9/2) ** 2</gadget>
<output>81/4 = around 20.25</output>

<gadget id="calculator">3.14 * (81/4)</gadget>
<output>63.585</output>

<gadget id="calculator">423.9 + 63.585</gadget>
<output>487.485</output>

<result>487.485</result>