A good knowledge on calculation to conduct research works effectively is important for undergraduate and postgraduate students. Different calculations in different fields like Agronomy, Soil Science, Weed Science, Plant Physiology, Plant Pathology, Genetics, Entomology, and other branches of Crop Science have been presented. These calculations are presented through exercises, and the exercises are solved through mathematical equations. Learning of essential mathematical equations are made easy and interesting. Therefore, this book is an all in one book for the undergraduate and postgraduate students including researchers aiming at enhancing their knowledge on basic calculation used in agriculture science area worldwide. The direction of this book will help the students, researchers, and extension workers in the field of agriculture to solve many problems.