The road from the bottom of the mountain to the top of the mountain is 3 kilometers long. It took Ding Ding 3 hours to go up the mountain and 2 hours to go down the mountain. What is his average speed up and down the mountain in kilometers per hour?
从山底到山顶的路长3千米．小丁丁上山用了3小时，下山用了2小时，他上下山的平均速度是多少千米/小时．
<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<gadget id="calculator">3 + 2</gadget>
<output>5</output>

<gadget id="calculator">6 / 5</gadget>
<output>6/5 = around 1.2</output>

<result>6/5 = around 1.2</result>