Mathematics Class 7 - Data Handling Notes

Data Handling

Welcome to the chapter on Data Handling for Class 7. In this chapter, you will learn how to collect, organize, represent, and interpret data. By the end of this chapter, you will be able to use tables, graphs, and charts to make sense of information and solve problems!

Introduction

Data handling means working with information. We collect data, organize it, and show it in different ways so it is easy to understand. Data helps us make decisions and solve problems.

Collecting Data

Data can be collected from surveys, experiments, or observations. For example, you can collect data about your classmates' favorite fruits.

• Ask questions and record answers.
• Use tally marks to count responses.

Organizing Data

After collecting data, organize it in tables or lists. This makes it easier to read and understand.

• Use tables to show data clearly.
• Arrange data in order (ascending or descending).

Representing Data

Data can be shown using different types of graphs and charts:

• Bar Graph: Uses bars to show numbers.
• Pictograph: Uses pictures or symbols to show data.
• Pie Chart: Shows data as parts of a circle.
• Line Graph: Shows data points connected by lines.

Interpreting Data

Interpreting data means understanding what the data shows. Look for patterns, compare numbers, and answer questions based on the data.

• Which is the most popular fruit?
• How many students chose apples?
• Which graph shows the data best?

Probability (Introduction)

Probability is the chance of something happening. For example, the probability of getting a head when tossing a coin is 1 out of 2.

• Probability is written as a fraction or percentage.
• It helps us predict outcomes.

Fun Activity: Survey and Graph!

Survey your friends about their favorite sport. Make a table and draw a bar graph to show the results.

Summary

• Data handling involves collecting, organizing, representing, and interpreting data.
• Graphs and charts help us understand data easily.
• Probability tells us the chance of an event happening.

Practice Questions

1. Make a table showing the number of pets owned by 10 students.
2. Draw a bar graph for the table above.
3. What is a pictograph?
4. If 5 out of 20 students like cricket, what fraction is this?
5. What is the probability of getting a 3 when rolling a dice?

Challenge Yourself

• Collect data about your family's favorite foods and represent it using a pie chart.
• Find the probability of getting a tail when tossing a coin.

Did You Know?

• Data handling is used in sports, weather reports, and even in elections!
• Probability helps us make smart guesses about the future.

Glossary

• Data: Information collected for study.
• Graph: A picture that shows data.
• Probability: The chance of something happening.
• Pictograph: A graph that uses pictures to show data.

Answers to Practice Questions

1. (Student should make a table with names and number of pets.)
2. (Student should draw a bar graph based on the table.)
3. A pictograph is a graph that uses pictures or symbols to show data.
4. 5/20 or 1/4
5. 1/6

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Practice data handling to become a smart problem solver!