On a map with a scale of 1:50000, the measured distance between A and B is 4 cm. What is the actual distance between A and B in meters?
在比例尺1：50000的地图上，量的A、B两地的距离为4厘米，A、B两地的实际距离是多少米．
<gadget id="calculator">1 / 50_000</gadget>
<output>1/50_000 = around 0.00002</output>

<gadget id="calculator">4 / (1/50_000)</gadget>
<output>200_000</output>

<gadget id="calculator">200_000 / 100</gadget>
<output>2_000</output>

<result>2_000</result>