Question

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
2004	650

Represent the above data by a pictograph

(a) Prepare a pictograph of student using on symbol an icon of a student to represent 100 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 representing 50 students. Which pictograph do you find more informative?

Answer 1

(a) Let one icon represent 100 students.
Then, the number of icons for different years are as follows:

Year	Number of students
1996	400 ÷ 100 = 4
1998	550 ÷ 100 = $5\frac{1}{2}$
2000	450 ÷ 100 = $4\frac{1}{2}$
2002	600 ÷ 100 = 6
2004	650 ÷ 100 = $6\frac{1}{2}$

The pictograph representing the above data is as follows:

Year	Number of students
1996
1998
2000
2002
2004

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

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

(b) Let one icon represent 50 students.
Then, the number 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
2004	650 ÷ 50 = 13

The pictograph showing the above data is as follows:

Year	Number of students
1996
1998
2000
2002
2004

The second pictograph is more informative.

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