Q.What is a histogram? Explain briefly how it differs from a frequency polygon.

A histogram and a frequency polygon present the same continuous frequency distribution in two related but visually different forms.

A histogram is drawn by marking the class intervals of a continuous frequency distribution along the X-axis, with no gaps between adjacent bars (since the classes are continuous), and drawing a rectangle over each class whose height is proportional to its frequency (or, for unequal class widths, its frequency density).

A frequency polygon presents the same distribution as a many-sided line figure. It can be constructed either by joining the midpoints of the tops of a histogram's bars with straight lines, or, independently, by plotting each class's frequency directly against its own mid-value and joining the points — closing the figure to the base line one class-width beyond the first and last classes on either side.

Key differences:

1. A histogram is made of solid rectangles; a frequency polygon is a line figure. …

Using the class LIMITS instead of the class MID-VALUES when plotting a frequency polygon directly (without first drawing a histogram) shifts every point half a c …