To prepare a diluted solution, the mass ratio of medicine powder to water is 1:25. If 520 kilograms of this diluted solution is prepared, how many kilograms of medicine powder are needed?
配制一种稀释液，药粉和水的质量比是1：25，如果配制这种稀释液520千克，需要药粉多少千克？
<gadget id="calculator">1 + 25</gadget>
<output>26</output>

<gadget id="calculator">1 / 26</gadget>
<output>1/26 = around 0.038462</output>

<gadget id="calculator">520 * (1/26)</gadget>
<output>20</output>

<result>20</result>