It used to take 5 hours for a car to travel from point A to point B, but now it only takes 4 hours. How much faster is the current speed than the original speed?
一辆汽车从A地到B地，原来用5小时，现在只用4小时，现在的速度比原来的速度变快多少．
<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>