On a map with a scale of 1:400000, the distance between A and B is 6 cm. What is the actual distance between A and B?
比例尺是1：400000的地图上，量得A、B两地间的距离是6厘米，A、B两地间的实际距离是多少．
<gadget id="calculator">400_000 / 100_000</gadget>
<output>4</output>

<gadget id="calculator">4 * 6</gadget>
<output>24</output>

<result>24</result>