This type of Histogram is based on the data with unequal intervals. When the data of class intervals are unequal, width of the rectangles would be different. The width of the rectangles would increase or decrease in the size of intervals. Before presenting the data in the form of graphs, frequency of unequal class intervals are adjusted.
How does the procedure of drawing a histogram differ when class intervals are unequal in comparison to equal class intervals in a frequency table?