A child goes on an autumn outing, travels 3 kilometers per hour when going there, and arrives in 2 hours; it takes 3 hours to return, how many kilometers will he travel per hour when returning?
小朋友去秋游，去时每小时行3千米，2小时到达；返回时用时3小时，返回时每小时行多少千米？
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

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

<result>2</result>