On a map with a scale of 1:6000000, the distance between the two places is measured to be 2.5 cm. It takes 2 hours for a train to complete its journey. Find the speed of the train.
在比例尺是1：6000000的地图上，量得两地的距离是2.5厘米，一列火车行完全程用了2小时，求火车的速度．
<gadget id="calculator">1 / 6_000_000</gadget>
<output>1/6_000_000 = around 0</output>

<gadget id="calculator">2.5 / (1/6_000_000) / 100_000 / 2</gadget>
<output>75</output>

<result>75</result>