A barrel of gasoline is packed in the same oil bottle. If 6 bottles are filled, there will be 4/5 of the oil left in the barrel. If 5 bottles are filled, there will be 75 kilograms left. How many kilograms does the barrel of oil weigh?
一桶汽油，用同样的油瓶装，如果灌满6瓶，还剩这桶油的(4/5)，如果灌满5瓶，还剩75千克，这桶油共重多少千克？
<gadget id="calculator">4 / 5</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">(1/5) / 6</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(1/30) * 5</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 - (1/6)</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">75 / (5/6)</gadget>
<output>90</output>

<result>90</result>