Two barrels of oil weigh (5/8) tons in total, and barrel A weighs (1/5) tons, how much lighter than barrel B?
两桶油共重(5/8)吨，甲桶油重(1/5)吨，比乙桶油轻多少吨？
<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(5/8) - (1/5) - (1/5)</gadget>
<output>9/40 = around 0.225</output>

<result>9/40 = around 0.225</result>