Grade 7 Joint Bar Graph

Step-by-Step Learning

Learn how to draw and interpret Joint Bar Graphs using an example.

Example 1: What is a Joint Bar Graph?

Explain the purpose and features of a Joint Bar Graph.

Concept: A Joint Bar Graph (also called a Double Bar Graph) is used to compare two sets of data simultaneously. It uses pairs of bars side-by-side for each category.

Purpose: It helps in easily comparing the values of two different groups or conditions for the same categories.

Key Features:

**Two bars** for each category.
A **Key or Legend** to identify which bar represents which set of data.
**Axes** (Horizontal and Vertical) with appropriate labels and scale.

Example 2: Drawing a Joint Bar Graph

Draw a joint bar graph for the following data showing the number of students who like different sports in two classes (Class 7A and Class 7B).

Sport	Class 7A	Class 7B
Cricket	30	25
Football	20	28
Basketball	15	18
Badminton	10	12

Step 1: Draw the X-axis (Horizontal Axis) and the Y-axis (Vertical Axis).

Step 2: Label the X-axis. This axis usually represents the categories (in this case, 'Sport'). Leave some space between categories.

Step 3: Label the Y-axis. This axis represents the frequency (in this case, 'Number of Students'). Choose an appropriate scale based on the data values. The maximum value is 30, so a scale like 0, 5, 10, 15, ... 35 would be suitable.

Step 4: Draw pairs of bars for each category. For 'Cricket', draw one bar up to 30 for Class 7A and a bar next to it up to 25 for Class 7B. The bars in a pair should touch, but there should be space between different pairs.

Step 5: Use different colors or patterns for the bars representing Class 7A and Class 7B.

Step 6: Create a **Key or Legend** to show which color/pattern represents which class.

Step 7: Give the graph a clear **Title**, such as "Number of Students Liking Different Sports in Class 7A and 7B".

Visualization: (A visual representation would appear here in a drawing tool or interactive element)

Imagine a bar graph here with pairs of bars for each sport, comparing Class 7A and Class 7B counts.

Example 3: Interpreting a Joint Bar Graph

Look at the joint bar graph from Example 2. Answer the following questions:

Which sport is most popular in Class 7A?
Which sport is most popular in Class 7B?
Which sport has the least total number of students across both classes?
In which sport is the difference in popularity between the two classes the greatest?

Refer back to the imagined graph from Example 2 to answer these questions.

Answer 1: Look at the bars for Class 7A. The tallest bar for Class 7A is for Cricket (30 students). So, Cricket is most popular in Class 7A.

Answer 2: Look at the bars for Class 7B. The tallest bar for Class 7B is for Football (28 students). So, Football is most popular in Class 7B.

Answer 3: Calculate the total for each sport:

Cricket: 30 + 25 = 55
Football: 20 + 28 = 48
Basketball: 15 + 18 = 33
Badminton: 10 + 12 = 22

The least total is 22, for Badminton. So, Badminton has the least total number of students.

Answer 4: Calculate the difference for each sport:

Cricket: |30 - 25| = 5
Football: |20 - 28| = 8
Basketball: |15 - 18| = 3
Badminton: |10 - 12| = 2

The greatest difference is 8, for Football. So, the difference is greatest in Football.

Practice Mode

Think about scenarios where you would use a joint bar graph.

Example Prompt: Describe a situation where you would use a joint bar graph to compare data.

Your Scenario:

Grade 7 Joint Bar Graph

Step-by-Step Learning

Example 1: What is a Joint Bar Graph?

Example 2: Drawing a Joint Bar Graph

Example 3: Interpreting a Joint Bar Graph

Practice Mode

Related Concepts

Data

Statistics

Frequency

Scale

Axes

Legend / Key

Pictograph

Bar Graph