📘 Class 9 · Mathematics
Chapter 14: Probability
2 lessons
Probability closes the Class 9 syllabus with the classical formula — favourable outcomes divided by total equally likely outcomes — applied to coins, dice and cards, alongside experimental probability observed from repeated trials. Tossing one coin gives P(heads)=1/2 instantly, without needing to actually toss it.
Miscounting the total outcomes is the most common error, especially with two dice (36 outcomes, not 12), and assuming every possible sum of two dice is equally likely is a related misconception worth unlearning early. As the final chapter of the year, this introduces a genuinely new branch of mathematics — reasoning about uncertainty — that Class 10's own Probability chapter builds on directly with complementary events.