If a pesticide is prepared into a potion at a ratio of 1:500, how many kilograms of this pesticide should be placed in 100.2 kg of potion? (Answer with proportional knowledge)
把一种农药按1：500配制成药水，在100.2千克的药水中，应放这种农药多少千克？(用比例知识解答)
<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">100.2 * (1/501)</gadget>
<output>0.2</output>

<result>0.2</result>