CBSE Class 6 Mathematics Data Handling Worksheet Set 01

Chapter - 9 (DATA HANDLING)

Question 1. Fill in the blanks.
i) Representation of data in form of pictures is called ___________.
ii) In a bar graph width of rectangle is always ____________.
iii) The tally mark represented ________.
Answer:
i) pictograph
ii) equal / uniform
iii) 5
In simple words: A pictograph uses pictures to represent numbers, bar graphs use equal-width rectangles, and a group of five tally marks has four vertical lines crossed by a diagonal line.

Exam Tip: Remember standard definitions from statistics to quickly answer fill-in-the-blank questions.

Question 2. Complete the following Table.
Answer:
Let us complete the frequency table by counting the tally marks in each row. Note that a group of 5 tally marks is represented as four vertical lines with a diagonal cross line.

In simple words: Count each vertical stroke as 1 and each crossed bundle as 5 to find the total frequency.
Exam Tip: Always double check crossed tally marks as 5 units before writing the final frequency.

Question 3. Students on roll of a school during 4 years is given in the following pictograph.
Year 2006: 3 full symbols
Year 2007: 4 full symbols
Year 2008: 3 full symbols and 1 half symbol
Year 2009: 5 full symbols and 1 half symbol
(Note: Each full symbol represents 100 students, and a half symbol represents 50 students.)
Answer the following questions.
a) How many students were on roll in year 2007 ?
b) How many students were more in 2009 than 2008?
Answer:
a) Number of students in year 2007 = 4 symbols \(\times 100\) = 400 students.
b) Number of students in year 2008 = 3.5 symbols \(\times 100\) = 350 students.
Number of students in year 2009 = 5.5 symbols \(\times 100\) = 550 students.
Difference = 550 - 350 = 200 more students.
In simple words: Multiply the number of symbols by 100 to get the student count for each year, then compare or subtract as needed.

Exam Tip: Pay close attention to half symbols in pictographs, as they represent half of the key value (50 students).

Question 4. Bar graph shows the number of students in different classes of a school. Read the graph and answer the following questions.
a) How many students are in class X?
b) How many students are in class VII?
c) How many students are in class IX?
Answer:
According to the given bar graph, 1 unit on the vertical axis represents 10 students.
a) The bar for Class X reaches a height of 8 units. Therefore, number of students in class X = \(8 \times 10 = 80\) students.
b) The bar for Class VII reaches a height of 8 units. Therefore, number of students in class VII = \(8 \times 10 = 80\) students.
c) The bar for Class IX reaches a height of 10 units. Therefore, number of students in class IX = \(10 \times 10 = 100\) students.
In simple words: Read the height of the bar for each class and multiply by the scale factor (10 students per unit) to find the total number of students.

Exam Tip: Always check the scale given on the vertical axis before reading values from a bar graph.