Course Content
CBSE Class 8 Maths
About Lesson

Understanding Probability

Probability is the measure of how likely an event is to occur. It is expressed as:

 

 

 

For example, if during a rainy season, it rains 1 out of 10 days, the probability of rain on a given day is:

P(Rain)=110=0.1or10%

Similarly, the probability of no rain on that day is:

P(No Rain)=1−P(Rain)=910=0.9or90%

This concept helps us in making predictions and decisions in various real-life situations.

Real-Life Applications of Probability

1. Election Predictions (Exit Polls)

  • A small sample of voters is surveyed after they cast their vote.
  • This sample represents the larger population, and probability helps estimate which candidate is likely to win.
  • Example: If 60% of the sample votes for Candidate A, the probability of Candidate A winning can be estimated based on this data.

2. Weather Forecasting

  • The Meteorological Department collects data over many years.
  • By analyzing past trends, they predict future weather conditions.
  • Example: If it has rained on 30% of similar days in the past, then the probability of rain on a given day is 0.3 (30%).

3. Insurance and Risk Assessment

  • Insurance companies use probability to assess risks and set premiums.
  • Example: If data shows that only 5% of drivers in a city have accidents annually, the probability of a driver having an accident in a year is 0.05 (5%).

4. Medical Diagnosis and Drug Testing

  • Probability is used in medical trials to determine the effectiveness of drugs.
  • Example: If a new medicine cures 8 out of 10 patients, its success probability is 0.8 (80%).

5. Games of Chance (Lottery & Gambling)

  • In a lottery where 1 ticket wins out of 100, the probability of winning is: P(Winning)=1100=0.01or1%P(text{Winning}) = frac{1}{100} = 0.01 quad text{or} quad 1%

Conclusion

Probability is a powerful tool used in various real-life applications, from predicting the weather to making business and healthcare decisions. Understanding probability helps in making informed choices and managing risks effectively.