Dried greens need to be reduced by 80%. Mom bought 50 kilograms of greens. How many dried vegetables can be dried?
青菜晒成青菜干要减轻80%，妈妈买来50千克青菜，可以晒成多少菜干？
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 - (4/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">50 * (1/5)</gadget>
<output>10</output>

<result>10</result>