Driving from Nanjing to Huai'an, car A travels for 4 hours to arrive, and car B travels for 5 hours to arrive, how much slower is the speed of car B than car A?
从南京开往淮安，甲车行了4小时到达，乙车行了5小时到达，乙车速度比甲车慢百分之几？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/4) - (1/5)</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">(1/20) / (1/4)</gadget>
<output>1/5 = around 0.2</output>

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