The tail of a fish weighs 2 kilograms. The weight of the head is equal to the weight of the tail plus half of the weight of the body, and the weight of the body is equal to the sum of the weight of the head and tail. What is the weight of the fish?
一条鱼的鱼尾重2千克，鱼头的重量等于鱼尾的重量加上鱼身重量的和的一半，而鱼身的重量等于鱼头和鱼尾重量的和，鱼的重量是多少？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) * 2</gadget>
<output>1</output>

<gadget id="calculator">1 + 2</gadget>
<output>3</output>

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

<gadget id="calculator">3 / (1/2)</gadget>
<output>6</output>

<gadget id="calculator">6 - 2</gadget>
<output>4</output>

<gadget id="calculator">4 + 6 + 2</gadget>
<output>12</output>

<result>12</result>