Statistics_and_Probability_Class8_DAV.pptx

Introduction to concepts of statistics

1. Statistics and Probability Class 8 Mathematics (CBSE/DAV) Prepared by: [Your Name] Subject: Mathematics

2. Learning Objectives • Understand data and its representation • Construct and interpret bar graphs and pie charts • Calculate mean, median, and mode • Understand and calculate probability through real-life examples

3. Introduction to Data and Statistics Statistics helps us collect, organize, and interpret data. Examples: Survey of students’ favorite sport, temperature records, test marks.

4. Types of Data • Raw Data – Unorganized data collected from source • Grouped Data – Data organized in a frequency table • Frequency – Number of times a value occurs

5. Steps in Data Handling 1. Collection of data 2. Organization of data 3. Representation using tables and graphs 4. Interpretation and analysis

6. Pictograph • Uses pictures or symbols to represent data. Example (from DAV Book): Number of books read by students in a week. 1 symbol = 2 books.

7. Bar Graph • Shows data using rectangular bars. Example: Marks scored by 5 students in a test. • Can be vertical or horizontal.

8. Double Bar Graph • Compares two related sets of data. Example: Marks of boys and girls in Mathematics and Science.

9. Pie Chart (Circle Graph) • Represents data as parts of a circle. Example: Time spent in daily activities – study, play, sleep.

10. Measures of Central Tendency Mean = Sum of observations ÷ Number of observations Median = Middle value when data arranged in order Mode = Most frequent observation

11. Example from DAV Book Marks obtained by 10 students: 12, 14, 10, 16, 18, 14, 10, 12, 16, 14 Mean = 13.6 Median = 14 Mode = 14

12. Real-Life Applications • Weather forecasting uses statistics • Sports records and averages • Business sales analysis

13. Introduction to Probability Probability means the chance of an event happening. Example: Getting a head on tossing a coin.

14. Key Terms Experiment – Action with outcomes Trial – Repetition of experiment Outcome – Result obtained Event – Desired result

15. Probability Formula Probability = (Number of favorable outcomes) / (Total number of outcomes) Example: P(getting head) = 1/2

16. Examples • Tossing a coin – Probability of head = 1/2 • Rolling a die – Probability of getting 3 = 1/6 • Drawing a red card – 26/52 = 1/2

17. Activity / Quiz Q1: What is the mean of 10, 20, 30? Q2: Probability of getting an even number on a die? Q3: Draw a bar graph for students' favorite fruits.

18. Summary • Data can be represented through graphs and charts. • Mean, median, and mode describe data. • Probability measures chance. • Both topics are used in daily life decisions.

19. Assessment 1. Construct a double bar graph using your class data. 2. Find mean, median, and mode of marks in Mathematics. 3. Find probability of getting tails when a coin is tossed.

20. Thank You Reflect: Where do you see statistics and probability in real life? (Weather, games, reports, etc.)