On a map with a scale of 1:5,000,000, the measured distance between A and B is 3 cm. If it is drawn on a map with a scale of 1:2,000,000, how many centimeters should be drawn?
在一幅比例尺是1：5000000的地图上，量的甲乙两地的距离是3cm，如果把它画在比例尺是1：2000000的地图上，应该画多少厘米？
<gadget id="calculator">1 / 5_000_000</gadget>
<output>1/5_000_000 = around 0</output>

<gadget id="calculator">3 / (1/5_000_000)</gadget>
<output>15_000_000</output>

<gadget id="calculator">1 / 2_000_000</gadget>
<output>1/2_000_000 = around 0</output>

<gadget id="calculator">15_000_000 * (1/2_000_000)</gadget>
<output>15/2 = around 7.5</output>

<result>15/2 = around 7.5</result>