Chapter 22 Data Handling II (Pictographs) Exercise 22.2

Question: 1

The following are the details or the number of students in a class of 30 students presents a week.

Day Number of students present
Monday 24
Tuesday 20
Wednesday 28
Thursday 30
Friday 26
Saturday 22

Represent the above data by a pictograph.

Solution:

Let an icon of a student represent 4 students. Then, the number of icons for each day is as follows:

Day Number of students present
Monday 24 / 4 = 6
Tuesday 20 / 4 = 5
Wednesday 28 / 4 = 7
Thursday 30 / 4 = 7.5
Friday 26 / 4 = 6.5
Saturday 22 / 4 = 5.5

The pictograph representing the above data is as follows:

Number of the students present
 

Question: 2

Total number of students of a school in different years is shown in the following table:

Year Number of students
1996 400
1998 550
2000 450
2002 600
2006 650

Represent the above data by a pictograph.

(a) Prepare a pictograph of students using one symbol an icon of a student to represent students and answer the following questions:

(i) How many symbols represent total number of students in the year 2002?

(ii) How many symbols represent total number of students for the year 1998?

(b) Prepare another pictograph of students using any other symbol each represents students. Which pictograph do you find more informative?

Solution:

(a) Let one icon represent 100 students.

Then, the numbers of icons for different years are as follows:

Year Number of students
1996 400 / 100 = 4
1998 550 / 100 = 5.5
2000 450 / 100 = 4.5
2002 600 / 100 = 6
2006 650 / 100 = 6.5

The pictograph representing the above data is as follows:

Number of students

(i) 6 icons represent the total number of students in the year 2002.

(ii) 5 and half icons represent the total number of students in the year 1998.

(b) Let one icon represent 50 students.

Then, the numbers of icons for different years are as follows:

Year Number of students
1996 400 / 50 = 8
1998 550 / 50 = 11
2000 450 / 50 = 9
2002 600 / 50 = 12
2006 650 / 50 = 13

The second pictograph is more informative.

Explanation: in the second pictograph, every icon is complete, therefore more convenient to understand.