Put 15kg of sugar into water to make sugar water containing 20% sugar, how many kg of water is needed?
将15kg糖放入水中，制成含糖20%的糖水，需要多少kg的水．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">15 / (1/5)</gadget>
<output>75</output>

<gadget id="calculator">75 - 15</gadget>
<output>60</output>

<result>60</result>