On Sunday, the students went to the countryside to climb a mountain. It took 1 hour to climb from the foot of the mountain to the top of the mountain, and it took 30 minutes to return along the original road. The speed of going up the mountain is much slower than going down the mountain.
星期日，同学们到郊外爬山游览，从山脚爬到山顶用了1小时，沿原路返回用了30分钟，上山比下山速度慢多少．
<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">1 / 60</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">(1/30) - (1/60)</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">(1/60) / (1/30)</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>