A barrel of oil, use up (3/5), leaving 10 kilograms, how many kilograms does the barrel of oil weigh?
一桶油，用去它的(3/5)，剩下10千克，这桶油原重多少千克？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 - (3/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">10 / (2/5)</gadget>
<output>25</output>

<result>25</result>