From city A to city B, it takes 10 hours for car A and 8 hours for car B. How much slower is the speed of car A than car B?
从A城到B城，甲车要10小时，乙车要8小时，甲车速度比乙车慢多少
<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/8) - (1/10)</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">(1/40) / (1/8)</gadget>
<output>1/5 = around 0.2</output>

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