Add 20 grams of salt to 1 kg of water, what is the percentage of water in the salt water?
把20克盐加入1千克水中，这时水占盐水的多少
<gadget id="calculator">1 * 1_000</gadget>
<output>1_000</output>

<gadget id="calculator">1_000 + 20</gadget>
<output>1_020</output>

<gadget id="calculator">1_000 / 1_020</gadget>
<output>50/51 = around 0.980392</output>

<gadget id="calculator">1 * (50/51)</gadget>
<output>50/51 = around 0.980392</output>

<result>50/51 = around 0.980392</result>