A barrel of gasoline weighs 120kg. After pouring out 80%, the remaining gasoline weighs 45kg. How many kilograms of gasoline are in the barrel?
一桶汽油连桶重120kg，倒出80%后剩下的汽油连桶重45kg，这个桶中原有汽油多少千克？
<gadget id="calculator">120 - 45</gadget>
<output>75</output>

<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">75 / (4/5)</gadget>
<output>375/4 = around 93.75</output>

<result>375/4 = around 93.75</result>