This is the second of four volumes of books designed to help the eager middle or high school student to Master Competition Mathematics. The problems in the book are curated from actual competition problems from various high school mathematics tournaments in Georgia from the years 1987 to 2022. Each chapter includes expository remarks, important problem-solving techniques, theorems, and formulas, with examples and exercises. These are follows by extensive problem sets in each chapter, divides into Junior Varsity and Varsity problems. This book contains 1209 problems in four chapters: 1) Counting, 2) Number Theory, 3) Probability, and 4) Numbers in Other Bases. Chapters 5 through 8 contain solutions to the problems.