Mathematics -- Class 4

Topic: Data Handling (Bar Graphs, Pictographs, and Tables)
Name: ____________________________Class: 4Date: ________________
Learning Objectives
A Friendly Introduction

In Class 3, you learned to read simple pictographs where one picture stood for one item. Now in Class 4, we will work with pictographs where one symbol can stand for 2, 5, 10, or even more items!

We will also learn to read and draw bar graphs. Imagine your class votes for their favourite fruit. A bar graph can show the results clearly so everyone can compare at a glance. Let us learn how data tells a story!

Organising Data in a Table

Before making a graph, we first collect data and put it in a table (also called a tally table or frequency table).

Example 1: Favourite Fruits of Class 4-B (40 students)
FruitTally MarksNumber of Students
Mango|||| |||| ||12
Banana|||| |||8
Apple|||| ||||10
Guava|||| |6
Orange||||4

Think: Which fruit is the most popular? Which is the least popular? How many more students like mango than orange?

Reading a Pictograph (1 Symbol = More Than 1)

In a pictograph, each symbol represents a certain number of items. A key tells you how much each symbol is worth.

Example 2: Books Read by Students in a Week

Key: Each * = 5 books

StudentSymbolsBooks Read
Amit* * *3 x 5 = 15
Priya* * * *4 x 5 = 20
Rahul* *2 x 5 = 10
Sneha* * * * *5 x 5 = 25

Sneha read the most books (25). Rahul read the fewest (10).

Difference between Priya and Rahul: 20 - 10 = 10 books.

Think: If the key says 1 symbol = 10 students, and you see 3 symbols, how many students does that represent?

Reading and Drawing Bar Graphs

A bar graph uses bars (rectangles) to show data. The height or length of each bar tells us the value.

Parts of a bar graph: Title (what the graph is about), X-axis (horizontal -- categories), Y-axis (vertical -- numbers/scale), and Bars.

Example 3: Trees Planted by Different Classes
ClassTrees Planted
Class 320
Class 435
Class 525
Class 640

To draw a bar graph: Draw the X-axis (classes) and Y-axis (number of trees, scale: 0, 5, 10, ... 40). Draw a bar for each class reaching up to its value.

From the graph: Class 6 planted the most trees. Class 3 planted the fewest.

Steps to Draw a Bar Graph:

  1. Draw two lines -- one horizontal (X-axis) and one vertical (Y-axis).
  2. Label the X-axis with categories and the Y-axis with a number scale.
  3. Choose a suitable scale (count by 5s or 10s).
  4. Draw bars of equal width for each category. Leave equal gaps between bars.
  5. Give the graph a title.
Key Words
WordMeaning
DataInformation collected about something
PictographA graph that uses pictures or symbols to show data
Bar GraphA graph that uses bars to compare data
Key (Legend)Tells what each symbol in a pictograph represents
ScaleThe numbers along the axis of a bar graph
Tally MarksMarks used to count data; every 5th mark crosses the previous 4

Mathematics -- Class 4 (continued)

Topic: Data Handling -- Key Points and Practice
Key Points to Remember
Practice Questions

A. Fill in the Blanks

  1. A graph that uses pictures to show data is called a .
  2. In a pictograph, the tells us the value of each symbol.
  3. A bar graph has two axes: the -axis and the -axis.
  4. If one symbol = 10 and there are 4 symbols, the total is .
  5. The height of a bar in a bar graph shows the of that category.

B. Read the Pictograph and Answer

The pictograph below shows the number of runs scored by players. Key: Each * = 10 runs.

PlayerSymbols
Virat* * * * *
Rohit* * * *
Sachin* * * * * * *
Dhoni* * *
  1. How many runs did Sachin score?
  2. Who scored the fewest runs?
  3. How many more runs did Virat score than Dhoni?
  4. What is the total runs scored by all four players?

C. Read the Table and Answer

The table shows the number of students who travel to school by different means.

Mode of TravelNumber of Students
Bus45
Auto30
Bicycle20
Walking25
Car15
  1. Which mode of travel is used by the most students?
  2. How many students travel by auto or bicycle?
  3. How many more students take the bus than walk?
  4. What is the total number of students?

D. Multiple Choice Questions

  1. In a pictograph, if 1 symbol = 5 and a row has 6 symbols, the value is:
    (a) 6(b) 11(c) 25(d) 30
  2. Which part of a bar graph shows the categories?
    (a) Title(b) Y-axis(c) X-axis(d) Scale
  3. What do tally marks |||| ||| represent?
    (a) 7(b) 8(c) 9(d) 6

E. Short Answer

  1. Why is it important to have a key in a pictograph?
  2. What scale would you choose for a bar graph if the highest value in your data is 50? Why?
Fun Activity -- Classroom Survey

Ask 20 classmates about their favourite sport. Record the data in the table below. Then use the data to draw a bar graph on a separate sheet.

SportTally MarksNumber of Students
Cricket
Football
Kabaddi
Badminton
Kho-Kho