3. There are three piles of books, totaling 240 books. Pile A has 30 more books than 3 times Pile B, and Pile C has 15 fewer books than Pile B. Therefore, Pile A has $\qquad$ books.
【Analysis】Let pile B be $x$ books, A $3 x+30$ books, and C $x-15$ books; in total $x+3 x+30+x-15=240$, solving for $x$ gives $x=45$. Therefore, pile A has $45 \times 3+30=165$ (books).