Put 30 grams of salt into 670 grams of water, what is the percentage of salt in the salt water?
把30克盐放入670克水中，盐占盐水的多少．
<gadget id="calculator">670 + 30</gadget>
<output>700</output>

<gadget id="calculator">30 / 700</gadget>
<output>3/70 = around 0.042857</output>

<result>3/70 = around 0.042857</result>