Carrier pigeons fly an average of 76.5km, which is 55% slower than the speed of swift, the fastest bird in long-distance flight. How many kilometers can swifts fly on average per hour?
信鸽平均飞行76.5km，比长距离飞行最快的鸟--雨燕的速度慢55%．雨燕平均每小时可飞行多少千米？
<gadget id="calculator">55 / 100</gadget>
<output>11/20 = around 0.55</output>

<gadget id="calculator">1 - (11/20)</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">76.5 / (9/20)</gadget>
<output>170</output>

<result>170</result>