A bee can vibrate its wings about 231 times per second, and a locust can vibrate less (10/11) than a bee per second. How many times can a locust vibrate per second?
蜜蜂每秒能振动翅膀大约231次，蝗虫每秒震动次数比蜜蜂少(10/11)，蝗虫每秒能震动多少次？
<gadget id="calculator">10 / 11</gadget>
<output>10/11 = around 0.909091</output>

<gadget id="calculator">1 - (10/11)</gadget>
<output>1/11 = around 0.090909</output>

<gadget id="calculator">231 * (1/11)</gadget>
<output>21</output>

<result>21</result>