The salt content of salt water is 12.5%, how many grams of water are needed to prepare 200 grams of salt water.
盐水的含盐率是12.5%，要配制200克盐水，需要多少克水．
<gadget id="calculator">12.5 / 100</gadget>
<output>0.125</output>

<gadget id="calculator">1 - 0.125</gadget>
<output>0.875</output>

<gadget id="calculator">200 * 0.875</gadget>
<output>175</output>

<result>175</result>