The interior angle of a polygon is 1620°, how many polygons is this?
一个多边形的内角1620°，这是一个几边形？
<gadget id="calculator">1_620 / 180</gadget>
<output>9</output>

<gadget id="calculator">9 + 2</gadget>
<output>11</output>

<result>11</result>