A bee flies 40 kilometers in 2 hours, which is twice the speed of a butterfly. How many kilometers does the butterfly fly per hour?
一只蜜蜂2小时飞行40千米，是一只蝴蝶飞行速度的2倍，这只蝴蝶每小时飞行多少千米？
<gadget id="calculator">40 / 2 / 2</gadget>
<output>10</output>

<result>10</result>