A wire forms a circle with a radius of 6 decimeters. If the wire forms a square, what is the length of its side?
一根铁丝围成一个圆，半径是6分米，如果这根铁丝围成一个正方形，它的边长是多少分米．
<gadget id="calculator">6 / 4</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">2 * 3.14 * (3/2)</gadget>
<output>9.42</output>

<result>9.42</result>