There are two food stores, A and B. Originally, store B has more oil than store A (2/5). Later, store B sells 20% of the same amount of oil as store A. At this time, store B still has 120 kg more oil than store A. , How many kilograms of original oil in Jiadian?
甲乙两个食品店，原来乙店存油数量比甲店多(2/5)，后来乙店卖出了与甲店20%同样多的油，这时乙店还比甲店多120千克油，甲店原有油多少千克？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">120 / (1/5)</gadget>
<output>600</output>

<result>600</result>