Xiaohong travels 22.5 kilometers from home to school. He goes to school by bicycle every day. It takes 1.5 hours to go back and forth. How many kilometers does Xiaohong travel on average per hour?
小红从家到学校22.5千米，他每天骑车上学，往返一次共需1.5时，小红平均每时行多少千米？
<gadget id="calculator">22.5 * 2</gadget>
<output>45</output>

<gadget id="calculator">45 / 1.5</gadget>
<output>30</output>

<result>30</result>