A car drives from place A to place B, traveling 50 kilometers per hour when going there, and traveling 60 kilometers per hour when returning. It took 11 hours to go back and forth. What is the distance between A and B in miles?
汽车从甲地开往乙地，去时每小时行50千米，返回时每小时行60千米，来回一共用了11小时．甲、乙两地的距离是多少千米．
<gadget id="calculator">1 / 50</gadget>
<output>1/50 = around 0.02</output>

<gadget id="calculator">1 / 60</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">(1/50) + (1/60)</gadget>
<output>11/300 = around 0.036667</output>

<gadget id="calculator">11 / (11/300)</gadget>
<output>300</output>

<result>300</result>