The current price of crude oil in the international market is about 78 US dollars a barrel, which is about (1/5) higher than that of a year ago. How much was the price of a barrel of crude oil in US dollars a year ago?
现在国际市场上原油价格约78美元一桶，比一年前涨了约(1/5)，一年前一桶原油价格是多少美元？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">78 / (6/5)</gadget>
<output>65</output>

<result>65</result>