NCERT Class 9 Mathematics Ganita Manjari: Chapter 7 — The Mathematics of Maybe: Introduction to Probability
This chapter introduces the concept of probability as a measurement of the likelihood of events, distinct from physical quantities. It explains that probability deals with uncertainty and chance, crucial for understanding situations with multiple possibilities. The text defines random events and random observations, where outcomes are unpredictable despite knowing all possibilities. Examples like coin tossing, die rolling, and lucky draws illustrate randomness. The chapter emphasizes that while we cannot predict the exact outcome of a random experiment, probability helps us estimate the likelihood of specific outcomes. It sets the stage for learning objective methods of measuring probability and understanding the probability scale, essential for making informed decisions in various aspects of life.
Quick info
| Board | CBSE / NCERT |
|---|---|
| Class | Class 9 |
| Subject | Mathematics |
| Book | Ganita Manjari |
| Chapter | Chapter 7 — The Mathematics of Maybe: Introduction to Probability |
| Language | English |
| PDF type | NCERT Textbook |
| Session | CBSE 2026 |
| Reading time | 3 minutes |
| Word count | 584 |
Learning outcomes
- Understand probability as a measure of likelihood.
- Identify random events and their unpredictable nature.
- Recognize the role of chance and uncertainty in everyday situations.
- Differentiate between subjective and objective probability.
- Grasp the concept of randomness in experiments like coin tossing and die rolling.
Vocabulary
| Word | Meaning |
|---|---|
| Probability | A measure of the likelihood of an event occurring. |
| Likelihood | The chance of something happening. |
| Event | A specific outcome or occurrence. |
| Random event | An event where outcomes are uncertain and unpredictable. |
| Outcome | A possible result of an experiment or event. |
| Randomness | The quality of lacking a pattern or predictability. |
| Experiment | An action or process that can be repeated and has uncertain outcomes (also called a trial). |
| Trial | A single performance of an experiment. |
The complete chapter text is read in the official NCERT PDF viewer below (streamed from ncert.nic.in). This page provides NCERT Help study material — summary, vocabulary, practice questions, and FAQs — not a full reproduction of the textbook.
Read chapter online
This PDF is loaded from the official NCERT website (ncert.nic.in). Use the page buttons below to read — download is disabled on NCERT Help.
Read page by page below. PDF is streamed from the official NCERT website — no download button on this page.
Practice questions
- What is probability used to measure? Answer: Probability is used to measure the likelihood of events.
- Give an example of a random event. Answer: Tossing a coin, rolling a die, or a lucky draw are examples of random events.
- What is the key feature of a random event? Answer: The key feature is unpredictability; you know the possible outcomes but not which one will occur.
- What does randomness refer to? Answer: Randomness refers to a situation where you cannot predict exactly what will happen, even if you know all possible outcomes.
Frequently asked questions
What is probability in mathematics?
Probability is a branch of mathematics that measures the likelihood of events occurring in situations involving chance or uncertainty.
What is the difference between a physical measurement and probability?
Physical measurements like length or volume measure concrete quantities, while probability measures the chance of an event happening.
What are random events?
Random events are situations where the outcome cannot be predicted with certainty, even though all possible outcomes are known.
Can we predict the outcome of a random event with 100% certainty?
No, by definition, random events have an element of chance, making 100% certainty impossible for a specific outcome.
Why is understanding probability important?
Understanding probability is crucial for dealing with uncertainty and making informed decisions in many aspects of life.
What is randomness in the context of probability?
Randomness refers to the unpredictability of outcomes in an experiment or situation, where each possible outcome has a chance of occurring.
Related resources
Important topics
Topics covered
NCERT Class 9 Mathematics — Ganita Manjari — Chapter 7 — The Mathematics of Maybe: Introduction to Probability. Verified by NCERT Help Editorial Team. Reviewed on 29 Jul 2026. Last updated 10 Aug 2026.