Countable Completion is Isomorphic to Full Completion (Lang Algebra)

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This is from Lang's $Algebra$, revised third edition, page 52. I will state my understanding of the problem.

Suppose $G$ is a group, and $F$ is a family of normal subgroups of $G$, partially ordered by the subset relation. Then $F$ is directed, so we define the inverse limit: $\lim_{H∈F}G/H$ by the canonical homomorphisms.

Suppose we have an $A⊆F$ and $A = \{H_i\}_{i∈\mathbb{Z_+}}$, where for all i, we have $H_{i+1}⊆H_i$. Then we also similarly define the inverse limit $\lim_{i∈\mathbb{Z_+}}G/H_i$.

The problem is to show that these two limits are isomorphic if A is cofinal, that is, if for all $H∈F$ there exists $H_i∈A$ such that $H_i⊆H$. The problem seems to be counterintuitive and I do not know how to start. I would be thankful for hints as well as answers.

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After user10354138's comment it is an easy task to arrive at the desired isomorphism.

As for the intuition, it follows directly from the proof; the $H$th entry of $x ∈ \lim_{H∈F}G/H$ contains information about all larger $K$ encompassing $H$ and therefore the "collapsed" form of $x$ in the countable limit contains information about the original $x$ that is entirely recoverable.