On a drawing with a scale of 1:50000, the distance between two points is 18 cm. What is the actual distance in kilometers between these two points?
在比例尺是1：50000的图纸上，量及两点之间的距离是18厘米，这两点的实际距离是多少千米．
<gadget id="calculator">1 / 50_000</gadget>
<output>1/50_000 = around 0.00002</output>

<gadget id="calculator">18 / (1/50_000) / 100_000</gadget>
<output>9</output>

<result>9</result>