A road roller rolled 540 square meters of road surface in 1.8 hours. The total area of a section of road is 2160 square meters. According to this calculation, how many hours will it take to finish rolling this section of road?
一台压路机1.8小时碾压路面540平方米．一段公路的总面积是2160平方米，照这样计算，碾压完这段公路，共需多少小时？
<gadget id="calculator">2_160 * 1.8</gadget>
<output>3_888</output>

<gadget id="calculator">3_888 / 540</gadget>
<output>36/5 = around 7.2</output>

<result>36/5 = around 7.2</result>