Mingyue and her father drove from Guyuan to Yinchuan, traveling 110 kilometers per hour and arriving in 3 hours. It took 5 hours to return. Ask how many kilometers per hour the cars they drive travel on average for a round trip?
明月和爸爸开车从固原到银川，去时每小时行110千米，3小时到达．返回时行了5小时．问他们所开的小汽车往返一次平均每小时行多少千米？
<gadget id="calculator">110 * 3 * 2</gadget>
<output>660</output>

<gadget id="calculator">3 + 5</gadget>
<output>8</output>

<gadget id="calculator">660 / 8</gadget>
<output>165/2 = around 82.5</output>

<result>165/2 = around 82.5</result>