Page 150 - Maths Skill - 6

148 Maths

BAR GRAPH
When the given data is large and also not in multiples of a number, then it is difficult to represent it by a pictograph.
Thus we use rectangles of uniform width to represent large data. We always keep equal space in between the bars
or rectangles of uniform width.

Properties of Bar graph
● Bars may be either vertical or horizontal, we often use vertical bars.
● The height (or length) of the bar indicates the value of the data.

● Width of the bar always remains equal but height (or length) changes according to the data.
● Bars are equally spaced.
● Bars may be shaded to make them attractive.
● Bars graphs are useful for visual comparison of the given data.

Construction of Bar graph
Follow the following steps to construct bar graph:

Step 1: On a graph paper, we draw horizontal line (X-axis) and a vertical line (Y-axis).
Step 2: Mark points at equal intervals along horizontal line. Below these points write the names of the data items
whose values are to be plotted.
Step 3: Choose a suitable scale. On that scale determine the height of the bars for the numerical values.
Step 4: Mark these heights parallel to the Y-axis from the points taken in Step 2.

Step 5: On the horizontal line, draw bars of equal width for the heights marked in Step 4.

INTERPRETATION OF BAR GRAPHS

The first step in reading a bar graph is to know what it represents or what is the information given by it. For this,
we read the Titles which are generally written just below the horizontal line (X-axis) and adjacent to vertical line
(Y-axis). After knowing that what does a bar graph represent, we read the scale so that we can know the precise
values in the given data.

After reading a bar graph one must be able to draw certain conclusions from it. Drawing some conclusions from
a given bar graph means interpretation of the bar graph.

Let’s Attempt

Example 1: The following table shows how a child spends his/her day.

Studying at Leisure time
At school Play time Hobby Eating Sleeping
home at home

1
1
6 hr 3 hr 2 hr 2 hr 1 hr 1 hr 8 hr
2 2

Construct a bar graph to represent the above information.