A kind of liquid medicine is made according to the ratio of powder and water is 1:500, and 1503 grams of liquid medicine is now prepared, how many grams of water is needed.
一种药水按药粉与水的比是1：500配成，现配1503克药水，需要水多少克．
<gadget id="calculator">1 + 500</gadget>
<output>501</output>

<gadget id="calculator">500 / 501</gadget>
<output>500/501 = around 0.998004</output>

<gadget id="calculator">1_503 * (500/501)</gadget>
<output>1_500</output>

<result>1_500</result>