Xiao Ming is 11.25 kilometers away from school. He goes to school by bicycle every day. It takes 1.5 hours to go back and forth. How many kilometers does Xiao Ming travel per hour on average?
小明离学校11.25千米，他每天骑车上学，往返一次共需1.5小时，小明平均每小时行多少千米．
<gadget id="calculator">2 / 1.5</gadget>
<output>1.333333</output>

<gadget id="calculator">11.25 * 1.333333</gadget>
<output>14.999996</output>

<result>14.999996</result>