On a map with a scale of 1:20000000, the distance from city A to city B is 2.8cm. How many hours will it take for a car to travel from city A to city B at a speed of 40 km/h?
在比例尺是1：20000000的地图上，甲市到乙市的距离是2.8cm．汽车以每小时40km的速度从甲市到达乙市，要用几小时？
<gadget id="calculator">1 / 20_000_000</gadget>
<output>1/20_000_000 = around 0</output>

<gadget id="calculator">2.8 / (1/20_000_000) / 100_000 / 40</gadget>
<output>14</output>

<result>14</result>