On a map with a scale of 1:10000000, the distance between A and B is 5 cm. If it is on a map with a scale of 1:4000000, how much is the distance between A and B?
在比例尺为1：10000000的地图上量得甲乙两地的距离是5厘米，如果在比例尺1：4000000的地图上，甲乙两地的距离长多少．
<gadget id="calculator">1 / 10_000_000</gadget>
<output>1/10_000_000 = around 0</output>

<gadget id="calculator">5 / (1/10_000_000)</gadget>
<output>50_000_000</output>

<gadget id="calculator">1 / 4_000_000</gadget>
<output>1/4_000_000 = around 0</output>

<gadget id="calculator">50_000_000 * (1/4_000_000)</gadget>
<output>25/2 = around 12.5</output>

<result>25/2 = around 12.5</result>