**Important Concepts and Formulas**

3. To get specific information from the
given data quickly, we arrange them in a tabular form using tally marks.

4. A pictograph represents data through
pictures of objects. Pictographs help us to answer the questions related to the
data at a glance.

5. Pictographs fail to represent large
data. Representing data by pictographs is difficult and time consuming process.

6. To represent data using a bar graph,
we have to draw bars or rectangles of uniform width leaving equal space
in-between the rectangles. The length of the bars represents the required
information about the quantity.

9. Every graph should have a title.
Using the title and the given scale, we can interpret a graph.