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YOUR ANSWER: n = n says "any number is equal to any number."
As long as we had to consider only the definition of n as a symbol for "any number," we could justifiably conclude that the algebraic statement n = n meant "any number equals any number." Now, however, we are restricted by the rule that when a letter is used to represent a number, it stands for the same number in each place that is appears in an equation.
Because we have precisely defined the meaning and use of the symbol n, the statement n = n makes a very precise statement, requiring an equally precise translation into english. Unfortunately---or possibly not--- the rules of english grammar do not require that word symbols always have the same meaning. The meanings of english words overlap and conflict. The same word has different meanings, different words have the same meaning. We achieve precision by introducing modifiers or by substituting other words which reflect more accurately what we have to say. The english sentence "Any number equals any number" is ambiguous. It's not clear whether the second time "any number" is used it refers to the same number or to a different number. So the algebraic statement n = n can only be translated by means of some such manipulation as:
Any number equals that same number.
Any number equals the same any number.
Any number equals itself.
Now return to page 24 and choose the other answer.