The book is ideal for students or professionals who need to refresh or expand their understanding of the mathematics they need for their daily work. The text is organized around the subjects that traditionally comprise precalculus mathematics. First up is a basic review of the arithmetic principles that are used in the subsequent specialty chapters. Each of these specialty chapters is self-contained and presents a clear and concise summary of core knowledge, including all definitions and formulas needed, followed by typical examples of solved problems. The problems are well motivated by practical applications and their solutions are developed in logical detail. Valuable shortcuts and insights from the author's personal experience are frequently supplied. All in all, The Practical Math Companion is intended to fill the need for a quick, authoritative, and comprehensive single reference that allows the user to avoid burdensome searches through ordinary textbooks and yet does not shortchange the user by giving bare bones methodology without adequate context. This book will be a friend to engineers, architects, scientists, business people, students, and anyone else with a need to solve practical quantitative problems.