Class 9 Mathematics Chapter 7 The Mathematics of Maybe: Introduction to Probability – Revision Notes

Quick revision notes for Class 9 Maths Chapter 7 (The Mathematics of Maybe: Introduction to Probability). These Class 9 Mathematics Chapter 7 notes are ideal for quick revision just before exams.

Key Terms

• Experiment/trial: action with uncertain result.
• Outcome: possible result.
• Event: collection of one or more outcomes.

Empirical Probability

• P(E) = (trials where E happened) / (total trials).
• 0 ≤ P(E) ≤ 1.
• P(E)=0: impossible (in data); P(E)=1: certain (in data).

One-Line Summary

Empirical probability is calculated directly from real experimental/observational data as a fraction (favourable trials/total trials), always falling between 0 and 1, and becomes more reliable as the number of trials increases.

Written by Satish

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