Probability Class 9th Notes - Free NCERT Class 9 Maths Chapter 15 Notes - Download PDF

Probability Class 9th Notes - Free NCERT Class 9 Maths Chapter 15 Notes - Download PDF

Updated on 21 Apr 2022, 01:23 PM IST

Probability class 9 notes:

The NCERT chapter on Probability is a numerical measure of the uncertainty of many phenomena. Its positive value might range from 0 to 1. The NCERT Class 9 Maths chapter 15 Notes provide a quick overview of the Probability chapter. In the Probability class 9 notes with some FAQs, the main topics covered are What is Probability, Experiment, Trial, Experimental Probability, Coin Tossing Experiment, Rolling of Dice Experiment, Sum of Probabilities of Favorable and Unfavorable Events, and Sum of Probabilities of Favorable and Unfavorable Events. Class 9 maths chapter 15 notes contain important formulas.. CBSE class 9 maths chapter 15 notes contain systematic explanations of topics using examples and exercises. Notes for class 9 maths chapter 15 includes FAQ’s or frequently asked questions about the chapter. These concepts can also be downloaded from Probability class 9 notes pdf download.

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NCERT Class 9 Maths Chapter 15 Notes

Probability

Probability is a statistic for calculating the likelihood of an event happening.

Although no event can be predicted with certainty, the idea of probability can be utilised to determine how likely it is that it will occur.

A probability of 0 indicates an improbable event, while a probability of 1 indicates a certain event.

Experiment
An experiment:

  • is any method that may be repeated indefinitely or any sequence of actions with a well-defined set of possible outcomes.

  • There can be only one or multiple possible outcomes.

  • The sample space is another name for it.

Trail

  • A trial is a single event that is performed to determine the outcome.

  • A sample space or experiment is a collection of all potential trials that result in a well-defined set of outcomes.

Experimental Probability
Experimental/Empirical Probability

The empirical probability of a possible event is given by:

Probability of an event occurring

P(E) = Number of positive outcomes divided by the total number of outcomes

Coin Tossing Experiment

Take a look at a fair coin.

Heads or tails are the only two outcomes that can occur.
Number of possible outcomes = 2

Number of outcomes to get head = 1

The probability of getting head is equal to the number of outcomes to get head divided by the number of possible outcomes =1/2

Rolling of Dice Experiment

When a fair dice is rolled, the number that appears first is between one and six.

Assume we roll the dice once to see if three numbers would appear.

Number of possible outcomes = 6
Number of outcomes to get three = 1
The probability of getting three is equal to the number of outcomes to get three divided by the number of possible outcomes =1/6

Sum of Probabilities of Favorable And Unfavourable Events
When a trial is undertaken with the intention of reaching a specific result, the objective is more likely to be met.

A favorable occurrence is when something goes your way in a trial or event.

When a trial is done with the intention of reaching a specific outcome, there is a risk that the objective will not be accomplished.

A trial or incident like this is an unfavorable event.

All positive and negative event outcomes can be traced back to a well-defined set of circumstances.

Assume that an event has n positive outcomes in sample space S.

Then there are the S-n unfavorable results.

The chance of favorable and unfavorable results is determined by the number of trials completed. The aggregate of these probabilities, on the other hand, is always one.

Significance of NCERT class 9 maths chapter 15 notes

The notes for Probability class 9th notes will assist you in reviewing the chapter and gaining an understanding of the key concepts.

This NCERT class 9th maths chapter 15 maths notes will help students to understand the formulas, statements, and rules in detail.

These topics can be downloaded from class 9 maths chapter 15 notes pdf download to study offline.

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