Uncle Li's car can travel 80 kilometers at the fastest speed. After repairing, it can travel 100 kilometers per hour at the fastest speed. How many percent has the speed increased?
李叔叔的汽车最快能行驶80千米，修好后，每小时最快能行驶100千米，速度提高了百分之几？
<gadget id="calculator">100 - 80</gadget>
<output>20</output>

<gadget id="calculator">20 / 80</gadget>
<output>1/4 = around 0.25</output>

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