50 kilograms, use up (1/5) kilogram, how many kilograms are left? What is the correct column
50千克，用去(1/5)千克，还剩多少千克？正确列式是多少
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">50 - (1/5)</gadget>
<output>249/5 = around 49.8</output>

<result>249/5 = around 49.8</result>