Put 20 grams of sugar in how many grams of water, the ratio of sugar to sugar water is 4:9.
把20克糖放入多少克水中，糖与糖水的比为4：9．
<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">(4/9) * 20</gadget>
<output>80/9 = around 8.888889</output>

<gadget id="calculator">20 - (80/9)</gadget>
<output>100/9 = around 11.111111</output>

<gadget id="calculator">(100/9) / (4/9)</gadget>
<output>25</output>

<result>25</result>