From city A to city B, car A takes 4 hours and car B takes 5 hours, so how much faster is car A than car B?
从A城到B城，甲车要用4小时，乙车要用5小时，那么，甲车速度比乙车快多少
<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) / (1/5)</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>