A potion is made up of liquid medicine and water in a ratio of 1:500. To prepare 4008 kilograms of this liquid medicine, how many kilograms of liquid medicine are needed?
一种药水是由药液和水按照1：500的比配成的．要配制这种药水4008千克，需要药液多少千克？
<gadget id="calculator">1 + 500</gadget>
<output>501</output>

<gadget id="calculator">1 / 501</gadget>
<output>1/501 = around 0.001996</output>

<gadget id="calculator">4_008 * (1/501)</gadget>
<output>8</output>

<result>8</result>