A barrel of oil weighs 2 kilograms when empty, which is exactly 1 kilogram less than 30% of the oil contained in this oil well. How many kilograms does this barrel of oil weigh in total?
一桶油，空桶重2千克，恰好比这个油涌所装油的30%少1千克，求这桶油连桶共重多少千克？
<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">3 / (3/10)</gadget>
<output>10</output>

<gadget id="calculator">10 + 2</gadget>
<output>12</output>

<result>12</result>