potion for spraying vegetables, the ratio of pesticide to water is 1:200. There are 2 kilograms of pesticides, how many kilograms of water need to be added?
一种喷洒蔬菜的药水，农药和水的比是1：200．现有2千克农药，需要加水多少千克？
<gadget id="calculator">2 / 1</gadget>
<output>2</output>

<gadget id="calculator">2 * 200</gadget>
<output>400</output>

<result>400</result>