A bag of potatoes, eating (2/5) of it, just eats 20 kilograms, how many kilograms does this bag of potatoes have?
一袋土豆，吃了它的(2/5)，刚好吃了20千克，这袋土豆原有多少千克．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">20 / (2/5)</gadget>
<output>50</output>

<result>50</result>