map uses a length of 5 cm to represent the actual distance of 20 kilometers. If the actual distance between the two places is 126 kilometers, how many centimeters should be drawn on this map.
一幅地图用5cm的长度表示实际距离为20千米的距离．如果两地实际距离为126千米，那么在这幅地图上应画多少厘米．
<gadget id="calculator">20 * 100_000</gadget>
<output>2_000_000</output>

<gadget id="calculator">5 / 2_000_000</gadget>
<output>1/400_000 = around 0.000002</output>

<gadget id="calculator">126 * 100_000 * (1/400_000)</gadget>
<output>63/2 = around 31.5</output>

<result>63/2 = around 31.5</result>