A circular flowerbed has a diameter of 20 meters, and (3/10) roses are planted in the area of the flowerbed. What is the area to plant roses?
一个圆形花圃，直径是20米，花圃面积的种(3/10)玫瑰，求种玫瑰的面积是多少？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 ** 2</gadget>
<output>100</output>

<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">3.14 * 100 * (3/10)</gadget>
<output>94.2</output>

<result>94.2</result>