Motivation for predicate logic. I am studying  predicate logic,I came across this para-

Propositional logic, studied in Sections 1.1–1.3, cannot adequately express the meaning of all statements in mathematics and in natural language. 
For example, suppose that we know that
  “Every computer connected to the university network is functioning properly.”
No rules of propositional logic allow us to conclude the truth of the statement “MATH3 is functioning properly",where MATH3 is one of the computers connected to the university network.

This is supposed to illustrate the motivation for predicate logic.
However,we can interpret the given statement as the conjunction of statements of the form "MATHx is connected to the university network and is working properly".
As this statement is true and is a conjunction the individual propositions have to be true;in terms of MATH3 too.
So propositional logic expresses the meaning of the statement adequately and we have also used the rules of propositional logic to conclude the truth about MATH3 contrary to whats been stated. 
What am I missing?I have gone through the notes by Stephen Simpson and Wikipedia but they proved inadequate.    



No rules of propositional logic allow us to conclude the truth of the statement “MATH3 is functioning properly",where MATH3 is one of the computers connected to the university network.

This is supposed to illustrate the motivation for predicate logic.
However,we can interpret the given statement as the conjunction of statements of the form "MATHx is connected to the university network and is working properly".

Yes, indeed, and this is the first step in moving from propositional logic to predicate logic.
You are no longer discussing a single statement about a single subject —a proposition—, rather you have moved to discussing a conjunction of similar statements about subjects that belong to a collection.
That is on the path to developing quantfied predicate statements.   Next is to move from discussing specific collections, to general collections, and formalise the rules of logic to manage the discussions.
