3、Distribute 61 books to the students of a class. If at least one person can receive at least 3 books, the maximum number of people in this class is $\qquad$.

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3、Distribute 61 books to the students of a class. If at least one person can receive at least 3 books, the maximum number of people in this class is $\qquad$.
【Analysis】Pigeonhole Principle. (60-1) $\div 2=30$ (people)