On a map with a scale of 1:9000000, the length of the route from City A to City B is measured to be 20 centimeters. How long does it take for an airplane to fly from City A to City B at a speed of 750 per hour?
在比例尺是1：9000000的地图上，量得甲城到乙城的航线长是20厘米，一架飞机以每小时750的速度从甲城飞往乙城，要多少小时到达？
<gadget id="calculator">1 / 9_000_000</gadget>
<output>1/9_000_000 = around 0</output>

<gadget id="calculator">20 / (1/9_000_000) / 100_000 / 750</gadget>
<output>12/5 = around 2.4</output>

<result>12/5 = around 2.4</result>