The required expression is [tex]18-3[/tex].
Important information:
We need to find the algebraic expressions for the given phrase.
The algebraic expressions for the phrase "a fewer than b" is:
[tex]b-a[/tex]
Similarly, the algebraic expressions for the phrase "3 fewer than 18" is:
[tex]18-3[/tex]
Therefore, the required expression is [tex]18-3[/tex].
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