On the 1:80000 map of the city's main urban area, the distance from Yangjiaping to Daping is measured to be 4.5 cm. What is the actual distance in kilometers from Yangjiaping to Daping?
在1：80000的我市主城区地图上，量得杨家坪到大坪的距离为4.5厘米．杨家坪到大坪的实际距离是多少千米．
<gadget id="calculator">1 / 80_000</gadget>
<output>1/80_000 = around 0.000013</output>

<gadget id="calculator">4.5 / (1/80_000) / 100_000</gadget>
<output>3.6</output>

<result>3.6</result>