On a map with a scale of 1:20000000, the distance from Beijing to Shanghai is 6 cm. How long does it take for a car to drive from Beijing to Shanghai at an average speed of 80 kilometers per hour?
在一幅比例尺是1：20000000的地图上，量得北京到上海的距离是6厘米．一辆汽车以平均每小时80千米的速度从北京开往上海，几小时到达？
<gadget id="calculator">1 / 20_000_000</gadget>
<output>1/20_000_000 = around 0</output>

<gadget id="calculator">6 / (1/20_000_000) / 100_000 / 80</gadget>
<output>15</output>

<result>15</result>