The car drove from Beijing to Nanjing and traveled 360 kilometers in 4 hours. At this time, there are still 270 kilometers away from Nanjing. How many hours will it take to travel from Beijing to Nanjing?
汽车从北京开往南京，4小时行了360千米，这时离南京还有270千米，照这样计算从北京到南京共要行多少小时？
<gadget id="calculator">270 + 360</gadget>
<output>630</output>

<gadget id="calculator">360 / 4</gadget>
<output>90</output>

<gadget id="calculator">630 / 90</gadget>
<output>7</output>

<result>7</result>