There is 3000 grams of 95% alcohol solution in a container, if it is diluted into a 75% alcohol solution, how many grams of water need to be added?
一个容器内有浓度为95%的酒精溶液3000克，若将它稀释成浓度为75%的酒精溶液，需要加水多少克？
<gadget id="calculator">95 / 100</gadget>
<output>19/20 = around 0.95</output>

<gadget id="calculator">75 / 100</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">(19/20) / (3/4)</gadget>
<output>19/15 = around 1.266667</output>

<gadget id="calculator">3_000 * (19/15)</gadget>
<output>3_800</output>

<gadget id="calculator">3_800 - 3_000</gadget>
<output>800</output>

<result>800</result>