The problems in this book are based on addition circuits. However, the problems have been designed to be about deduction rather than simple addition. The highly interconnected addition circuit problems from the second grade addition book have been presented as deduction problems. The difficulty level for these problems are much higher and meant for students in Middle School, while taking courses on Pre-algebra. All the problems are presented in a visual manner, using interconnected circuits. These circuits introduce notions of adding in series as well as parallel. The problems also require ability to order the sequence of additions among the circuit nodes. Such problems can help develop visual and spatial skills. Many of the problems in this book are circuit representations for generating algebraic functions such as n ], n DEGREES2, n DEGREES3, 2 DEGREESn, and so on. Although intimidating at first sight, these problems can be solved by forming systems of linear equations. The problems in this book have been limited to single variable expressions. The deduction problems have a simple format. The final or intermediate values based on addition of intermediate circuit nodes are provided for each problem. The goal is to find all the values based on addition of the inputs. A few solved examples using algebraic expressions are provided in the beginning for illustration purposes. These problems can also be solved visual