The mass ratio of liquid medicine to water in a liquid medicine is 1:20, now there are 40 grams of liquid medicine, how many grams of water should be added.
一种药水的药液和水的质量比是1：20，现在有药液40克，应加水多少克．
<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">40 / (1/20)</gadget>
<output>800</output>

<result>800</result>