It is a kind of pesticide, which is made up of liquid medicine and water according to the ratio of 1:100. To prepare 505 kilograms of this pesticide, how many kilograms of medicine are needed? (Answer with proportional knowledge)
一种农药，用药液和水按1：100配制而成．要配制这种农药505千克，需要药多少千克？(用比例知识解答)
<gadget id="calculator">100 + 1</gadget>
<output>101</output>

<gadget id="calculator">505 / 101</gadget>
<output>5</output>

<result>5</result>