The diameter of a wheel is 90cm, how many meters does the wheel move in one revolution?
一个车轮的直径为90cm，车轮转动一周，大约前进多少m．
<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">3.14 * (9/10)</gadget>
<output>2.826</output>

<result>2.826</result>