Uncle Wang set off from the county seat to Wangzhuang to deliver chemical fertilizers. When he went there, he drove 40 kilometers per hour. It took 3 hours, and he returned by the same road. It took 2 hours. How many kilometers per hour on average?
王叔叔从县城出发去王庄送化肥，去的时候每小时行使40千米，用了3小时，按原路返回，用了2小时，平均每小时行使多少千米？
<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">40 * (3/2)</gadget>
<output>60</output>

<result>60</result>