Written in a simple and lucid manner, it deals with Probability Theory spread over four chapters in accordance with the syllabi for classes IX to XII, enabling the students to understand the topic in a systematic and easy manner. The theory is well supported by a large number of numerical examples. This will clarify the theory part as well as the applications to the student, guiding them in solving the numerical problems. Each chapter has theory and numerical questions along with the objective type questions at the end (of each chapter). This will instill some more confidence about the subject matter. The book not only covers the units having statistics in the syllabi of mathematics paper for the classes IX to XII of CBSE but also takes care of statistics covered in economics paper. The book fulfills the requirement of State Boards courses also in which statistics is included in the paper of mathematics. It aims to serve as an ideal textbook for the senior secondary students for their statistics courses and help them secure higher percentage of marks/grades in Board examinations.