The express train takes 12 hours from Nanjing to Beijing, and the slow train takes 15 hours from Beijing to Nanjing. Now these two cars leave from Nanjing and Beijing at the same time and drive opposite each other. After 2 hours, they have traveled a total of 360 kilometers. How far is it between Nanjing and Beijing?
快车从南京开到北京要12小时，慢车从北京开到南京要15小时．现在这两车同时分别从南京和北京开出，相对而行，2小时后一共行了360千米．南京、北京相距多远？
<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(1/12) + (1/15)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">(3/20) * 2</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">360 / (3/10)</gadget>
<output>1_200</output>

<result>1_200</result>