2. The boy caught a fish. When asked how much the caught fish weighed, he said: “I think the tail weighs 1 kg, and the head weighs as much as the tail and half the body, and the body weighs as much as the head and the tail together.” How much does the fish weigh?
2. From the problem statement, it is known that the tail ( $X$ ) weighs 1 kg. The weight of the head is equal to the weight of the tail plus an additional $1 / 2$ of the body weight (T):

$$
\Gamma=\mathrm{X}+\mathrm{T} / 2 \text { or } 2 \Gamma=2 \mathrm{X}+\mathrm{T} .
$$

Since the tail weighs 1 kg, then $2 \Gamma=2+$ T .

From another condition, it is known that $\mathrm{T}=\Gamma+\mathrm{X}$ or $\mathrm{T}=\Gamma+1$.

From the obtained equations, we have:

$$
2 \Gamma=2+\Gamma+1, \Gamma=3, \mathrm{a} T=4 .
$$

Thus, the fish weighs $1+3+4=8$ (kg).

Answer: 8 kg.