Histograms and Frequency Polygons Demystified

1. If the length of some leaves of a plant is measured and the data is represented by a table having discontinuous class intervals, then how to draw a histogram for that data.

2. Suppose we draw a histogram with the help of a table which is having data in the form of discontinuous class intervals. Whether there is any other suitable graphical representation for the same data.

3. If the data in respect of lifetimes of some neon lamps is given in the form of a table, how to represent the information with the help of a histogram. How many lamps have a life time of more than specified hours?

4. If a table shows distribution of students in two sections according to the marks obtained by them, then how to use that data to form two frequency polygons on the same graph.

5. When the large amount of data is to be presented, we can condense the data in to groups and these groupings are called “classes” or “class-intervals” and their size is called the class-size or class width. In each of these groupings/classes, the least number is called the lower class limit and the greater number is called the upper class limit. In the case of histogram, the data has to be in the form of continuous class intervals. In the case of frequency polygon, it is not necessary for the data to be in continuous class intervals.