How many kilograms of water should be added to make 1500 grams of salt water with 8% salt content into salt water with 5% salt content?
把含盐8%的1500克盐水，制成含盐5%的盐水，应加入水多少千克？
<gadget id="calculator">8 / 100</gadget>
<output>2/25 = around 0.08</output>

<gadget id="calculator">5 / 100</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">(2/25) / (1/20)</gadget>
<output>8/5 = around 1.6</output>

<gadget id="calculator">1_500 * (8/5)</gadget>
<output>2_400</output>

<gadget id="calculator">2_400 - 1_500</gadget>
<output>900</output>

<gadget id="calculator">900 / 1_000</gadget>
<output>9/10 = around 0.9</output>

<result>9/10 = around 0.9</result>