The height of a cylinder is 18 cm, the radius of the base is the height (1/3), what is its lateral area?
一个圆柱的高是18厘米，底面半径是高的(1/3)，它的侧面积是多少．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">18 * (1/3)</gadget>
<output>6</output>

<gadget id="calculator">3.14 * 2 * 6 * 18</gadget>
<output>678.24</output>

<result>678.24</result>