Data Handling

In our daily life, we often come across information in the form of numbers, facts, or figures. This information is called data. Data handling is the process of collecting, organising, representing, and interpreting data in a systematic way. In earlier classes, we learned basic ideas of data. In this chapter, we study data handling in more detail, including graphical representation and an introduction to probability.

What is Data?

Data is a collection of facts or figures gathered for a specific purpose. Data can be related to marks obtained by students, heights of players, daily temperatures, rainfall, or survey results. Data helps us draw conclusions and make decisions.

Collection of Data

Data can be collected in different ways:

• Primary Data: Data collected by the investigator directly.
• Secondary Data: Data collected from books, newspapers, records, or the internet.

The accuracy of conclusions depends on correct data collection.

Organisation of Data

Raw data is often large and confusing. To make it meaningful, it is organised using tables. Data is grouped into classes, and frequencies are recorded. This helps in easy understanding and comparison.

Representation of Data

Data can be represented visually using graphs and charts.

1. Bar Graph

A bar graph uses rectangular bars to represent data. The height of each bar shows the value or frequency. Bar graphs are useful for comparing data easily.

2. Pie Chart

A pie chart represents data in the form of a circle divided into sectors. Each sector represents a part of the whole. Pie charts are useful for showing percentages and proportions.

3. Histogram

A histogram is similar to a bar graph but is used for continuous data. The bars touch each other, showing continuity.

Probability

Probability helps us measure the chance of an event occurring. It is defined as:

Probability = Number of favourable outcomes / Total number of outcomes

The probability of an event always lies between 0 and 1.

• Probability = 0 means the event is impossible.
• Probability = 1 means the event is certain.

Examples include tossing a coin or rolling a dice.

Applications of Data Handling

Data handling is used in statistics, business, science, economics, weather forecasting, sports analysis, and surveys. It helps us take informed decisions based on data.

Summary

In this chapter, we learned about data, its collection, organisation, graphical representation, and basic probability. Data handling helps us understand information clearly and logically.