30 tons is 20% more than how many tons.
30吨比多少吨多20%．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">30 / (6/5)</gadget>
<output>25</output>

<result>25</result>