On the scale (1/30000000) map, the length of the road from Guangzhou to Ya'an is measured to be 7 cm. What is the actual distance in kilometers from Guangzhou to Ya'an?
在比例尺(1/30000000)的地图上，量得广州到雅安的公路长是7厘米．广州到雅安的实际距离是多少千米．
<gadget id="calculator">1 / 30_000_000</gadget>
<output>1/30_000_000 = around 0</output>

<gadget id="calculator">7 / (1/30_000_000) / 100_000</gadget>
<output>2_100</output>

<result>2_100</result>