Xiaohong: My weight is 40kg. Xiao Ming: I am 10kg heavier than you. How many percent is Xiaohong lighter than Xiaoming?
小红：我的体重是40千克．小明：我比你重10千克．小红比小明轻百分之几？
<gadget id="calculator">40 + 10</gadget>
<output>50</output>

<gadget id="calculator">10 / 50</gadget>
<output>1/5 = around 0.2</output>

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