car drives from point A to point B. It takes 6 hours to go uphill and only 5 hours to go downhill when returning. How much is the speed increase when returning?
一辆汽车从A地开往B地，去时走上坡路，需要6小时，返回时走下坡路，只需要5小时，返回时的速度提高百分之几？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(1/5) - (1/6)</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(1/30) / (1/6)</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>