How much does 50 kg increase to 70 kg?
50千克增加多少以后是70千克．
<gadget id="calculator">70 - 50</gadget>
<output>20</output>

<gadget id="calculator">20 / 50</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>