Class 9 Maths - CBSE
Probability
In Class 9 Mathematics, the chapter on Probability introduces students to the quantitative study of chance and uncertainty. Moving beyond intuitive guesses, this chapter focuses on the Experimental or Empirical Probability approach, which is based on actual observations and real-life experiments. Students will learn how to collect data, perform trials, and calculate the ratio of the number of times an event happens to the total number of trials. This foundational topic is crucial for CBSE board exams, typically appearing in both 1-mark objective questions and 2 to 3-mark word problems involving coins, dice, and cards.
Start Learning FreeKey Concepts
Trial
A single performance of a random action, such as tossing a coin once or rolling a die.
Event
A collection of one or more outcomes of an experiment, representing the specific result we are looking for.
Empirical Probability
Probability calculated on the basis of the results of an actual experiment or historical data.
Range of Probability
The probability of any event always lies between 0 and 1, inclusive, where 0 means an impossible event and 1 means a sure event.
Complementary Events
Events representing the 'happening' and 'not happening' of a specific outcome, whose probabilities always add up to 1.
Important Formulas
Board Exam Info
In the CBSE Class 9 Mathematics question paper, the Probability chapter generally carries around 3 to 4 marks. Questions typically appear as 1-mark multiple-choice questions or short-answer word problems based on throwing dice, tossing coins, or surveying student data.
Frequently Asked Questions
Can the probability of an event ever be negative or greater than 1?
No, probability can never be less than 0 (negative) or greater than 1. It must always be a fraction or decimal between 0 and 1.
What is the difference between theoretical and experimental probability in Class 9?
In Class 9, you exclusively study experimental (empirical) probability, which depends on actual trials and observations. Theoretical probability, based on logical outcomes, is taught in Class 10.
What does a probability of 0 mean?
A probability of 0 means the event is impossible and can never happen during the experiment.
Learn Probability with Your AI Tutor
10 different ways to study this chapter. Free for 3 chapters per day.
Lecture
Key Points
Interactive
Quiz
Flashcards