This book presents methods of solving problems in classical combinatorics, combinatorial number theory, and combinatorial geometry. It can be seen as a continuation of the successful book "Equations and Inequalities" by the same authors. However, it can be read independently or used as a textbook in its own right. The authors' aim is to familiarize the reader with methods for solving problems in elementary mathematics, accessible to beginning university and advanced high-school students. They emphasize basic algebraic operations and other technical skills that are reinforced in numerous examples and exercises. Answers to all exercises can be found at the end of the book. The book is intended as a text for a problem-solving course at the first- or second-year university level, as a text for enrichment classes for talented high-school students, or for mathematics competition training.

Translated by: K. Dilcher