There are two barrels of oil, the weight of the first barrel is (3/4) of the second barrel, after pouring 20 kg from the first barrel into the second barrel, the first barrel of oil is (2/5) of the second barrel, How many kilograms do two barrels of oil weigh together?
有两桶油，第一桶油重量是第二桶的(3/4)，从第一桶倒入第二桶20千克后，第一桶油是第二桶油的(2/5)，两桶油共重多少千克？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">20 * (2/5)</gadget>
<output>8</output>

<gadget id="calculator">20 + 8</gadget>
<output>28</output>

<gadget id="calculator">(3/4) - (2/5)</gadget>
<output>7/20 = around 0.35</output>

<gadget id="calculator">28 / (7/20)</gadget>
<output>80</output>

<gadget id="calculator">(3/4) * 80</gadget>
<output>60</output>

<gadget id="calculator">60 + 80</gadget>
<output>140</output>

<result>140</result>