In 180 grams of water, add 20 grams of salt, how much salt accounts for the salt water
在180克水中，加入20克盐，盐占盐水的多少
<gadget id="calculator">180 + 20</gadget>
<output>200</output>

<gadget id="calculator">20 / 200</gadget>
<output>1/10 = around 0.1</output>

<result>1/10 = around 0.1</result>