Final answer:
The inequality to represent the number of books the first bookcase can hold, given that the second bookcase holds 2,492 books, is n < 2492.
Step-by-step explanation:
The first bookcase, labeled as a, can hold 1 less book than the second bookcase, which holds 2,492 books. To represent the number of books the first bookcase can hold using an inequality, we would set this up as n < 2492, where n stands for the number of books the first bookcase can hold.