To prepare a disinfectant, the ratio of liquid to water is 1:50, and the existing water is 300 kg, how many kg of liquid should be added?
配制一种消毒药，药液和水的比是1：50，现有水300千克，需要加药液多少千克？
<gadget id="calculator">1 / 50</gadget>
<output>1/50 = around 0.02</output>

<gadget id="calculator">300 * (1/50)</gadget>
<output>6</output>

<result>6</result>