Bar Charts - SS2 Economics Lesson Note

Bar charts are a type of graphical representation that uses rectangular bars to compare values. The bars can be horizontal or vertical, and their lengths represent the values being compared. 

Applications of bar charts:

• Comparing data: Bar charts are often used to compare data from different categories. For example, a bar chart can be used to compare the sales of different products or the performance of different teams.

Tracking changes over time: Bar charts can also be used to track changes over time. For example, a bar chart can be used to show the monthly sales of a product over the course of a year.

Summarizing data: Bar charts can be used to summarize large amounts of data into a more digestible form. For example, a bar chart can be used to summarize the results of a survey.

Communicating information: Bar charts can be used to communicate information to a wide audience. For example, a bar chart can be used to present financial data to shareholders or to present performance data to employees.

Making decisions: Bar charts can be used to make informed decisions. For example, a bar chart can be used to compare the costs and benefits of different options.

 

Word Problems on Bar Charts:

1. The following table shows the number of students who prefer different types of fruits. Formulate a bar chart to represent this data: 12 students prefer apples, 25 prefer oranges, 18 prefer bananas, 5 prefer grapes and 8 prefer pineapples.

Solution:

Step 1: Identify the variable and categories: The variable is the "number of students" and the categories are the different types of fruits: apples, oranges, bananas, pineapples, and grapes.

Step 2: Draw the horizontal and vertical axis: The horizontal axis represents the different types of fruits and the vertical axis represents the number of students. Label the horizontal axis as "Types of Fruits" and the vertical axis as "Number of Students."

Step 3: Draw the bars: For each fruit, draw a rectangle (bar) on the horizontal axis. The height of the rectangle (bar) represents the number of students. The bars should be spaced equally apart and have the same width.

Step 4: Label the chart: Title the chart as "Number of Students Who Prefer Different Types of Fruits." Label the horizontal axis as "Types of Fruits" and the vertical axis as "Number of Students."

2. A survey was conducted to find out the favourite sports of students in a school. From the survey the students were divided among 7 sports: 35 played soccer, 20 played basketball, 12 played tennis, 11 played badminton, 8 played baseball, and 15 played volleyball. Represent the data visually using a bar chart.

Solution:

Step 1: Identify the variable and categories: The variable is the "number of students" and the categories are the different types of sports: soccer, basketball, tennis, baseball, and volleyball.

Step 2: Draw the horizontal and vertical axis: The horizontal axis represents the different types of sports and the vertical axis represents the number of students. Label the horizontal axis as "Types of Sports" and the vertical axis as "Number of Students."

Step 3: Draw the bars: For each sport, draw a rectangle (bar) on the horizontal axis. The height of the rectangle (bar) represents the number of students. The bars should be spaced equally apart and have the same width.

Step 4: Label the chart: Title the chart "Favorite Sports of Students." Label the horizontal axis as "Types of Sports" and the vertical axis as "Number of Students."