There are two buckets, A and B, pour half of the water in bucket A into the empty bucket B, which is just filled with (2/5) of bucket B, and then pour out the full bucket (1/6) of the water in bucket B , and there are 15 kilograms left, how many kilograms can be contained in barrel A?
有甲乙两只桶，把甲桶的半桶水倒入空的乙桶，刚好装了乙桶的(2/5)，再把乙桶里的水倒出全桶的(1/6)后，还剩15千克，则甲桶可装多少千克．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(2/5) - (1/6)</gadget>
<output>7/30 = around 0.233333</output>

<gadget id="calculator">15 / (7/30)</gadget>
<output>450/7 = around 64.285714</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(2/5) / (1/2)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(450/7) * (4/5)</gadget>
<output>360/7 = around 51.428571</output>

<result>360/7 = around 51.428571</result>