Question

The following table gives the number of vehicles passing through a toll gate, every hour from 8.00 am. to 1.00 pm:

Time Interval	8.00 to 9.00	9.00 to 10.00	10.00 to 11.00	11.00 to 12.00	12.00 to 1.00
Number of vehicles	250	450	300	250	150

Draw a bar graph representing the above data.

Answer 1

In order to construct a bar graph representing the above data, we follow the following steps:

Step I: Take a graph paper and draw two mutually perpendicular lines OX and Oy. Let OX as the horizontal axis and OY as the vertical axis.

Step II: Along OX, mark time interval and along OY, mark number of vehicles.

Step III: Along OX, choose the uniform (equal) width of the bars and the uniform gap between them, according to the space available for the graph.

Step IV: Choose a suitable scale to determine the heights of the bars, according to the availability of space.

Here, we choose 1 unit length represents 50 vehicles.

Time interval	Height of bars
8.00 to 9.00	`250/50` = 5 units
9.00 to 10.00	`450/50` = 9 units
10.00 to 11.00	`300/50` = 6 units
11.00 to 12.00	`250/50` = 5 units
12.00 to 1.00	`150/50` = 3 units

Hence, the required bar graph for the given data is shown below

Scale: 1 unit length = 50 vehicles