Make 10 ventilation pipes of the same size with iron sheets, each section is 5 decimeters long, and the bottom diameter is 1.2 decimeters, how many square decimeters of iron sheets are needed at least?
用铁皮制10节同样大小的通风管，每节长5分米，底面直径1.2分米，至少需要多少平方分米铁皮？
<gadget id="calculator">3.14 * 1.2 * 5 * 10</gadget>
<output>188.4</output>

<result>188.4</result>