How many kilograms of water are added to 6 kg of salt water containing 12% salt to make the salt content of the salt water 5%.
含盐12%的盐水6千克，加入多少千克水后，使盐水含盐量变为5%．
<gadget id="calculator">12 / 100</gadget>
<output>3/25 = around 0.12</output>

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

<gadget id="calculator">(3/25) / (1/20)</gadget>
<output>12/5 = around 2.4</output>

<gadget id="calculator">6 * (12/5)</gadget>
<output>72/5 = around 14.4</output>

<gadget id="calculator">(72/5) - 6</gadget>
<output>42/5 = around 8.4</output>

<result>42/5 = around 8.4</result>