The Staff Selection Commission (SSC) conducts recruitment examinations for various posts such as SSC Combined Graduate Level Exam, SSC Combined Higher Secondary (10+2) Level, FCI Assistant Grade III, etc. where mathematical ability skills are tested in each examination. This book has been designed for the candidates who aspire to sit for various competitive and recruitment examinations conducted by the SSC. The present book covers the various aspects of Quantitative Aptitude like Mathematics, Algebra, Trigonometry, Geometry and Coordinate Geometry asked in various SSC examinations. The present book covering quantitative aptitude has been divided into 10 chapters namely Number System, Arithmetical Operations, Business Mathematics, Work, Speed and Time, Data Interpretation, Mensuration, Algebra, Geometry, Trigonometry and Coordinate Geometry each containing ample number of previous years' solved questions of examinations conducted by SSC. The chapters have been divided into units with individual practice questions. The previous years' (1999-2012) questions have been covered chapterwise. The questions covered in the book have been solved on the lines of basic principles and short-cut methods have been applied while solving the complicated problems. At the end of each a diagnostic test has been given which will help in chapterwise and topicwise revision of the concepts. At the chapterwise study, 10 Self Evaluation Tests have also been covered at the end of the book which will help in self analyzing the level of preparation and also in thorough practice of the syllabi of quantitative aptitude. This book is equally useful for all recruitment examinations conducted by SSC such as SSC CGL, CPO/SI, CHS, Multi-Tasking, FCI, Constable, etc. As the book contains ample number of quantitative aptitude questions asked in previous years' SSC examinations, it for sure will act as the best practice material for Mathematical Ability for competitive and recruitment exams conducted by SSC.