The oil tank is full of oil, (1/3) of this tank is filled with a pot of oil, after one cup of oil is filled in this oil pot, there is still (4/5) left in the oil pot, how many cups of oil can this oil tank hold ?
油箱中装满了油，这箱油的(1/3)倒满一壶油，这个油壶的油倒满一杯后，油壶里还剩(4/5)，这个油箱能装几杯油？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<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 / (1/3) / (1/5)</gadget>
<output>15</output>

<result>15</result>