Question

Describe the procedure of drawing a (1) frequency polygon, and (ii) frequency curve.​

Answer 1

Answer:

1. Steps to Draw a Frequency Polygon

•Mark the class intervals for each class on the horizontal axis. We will plot the frequency on the vertical axis.

•Calculate the classmark for each class interval. The formula for class mark is:

Classmark = (Upper limit + Lower limit) / 2

•Mark all the class marks on the horizontal axis. It is also known as the mid-value of every class.

•Corresponding to each class mark, plot the frequency as given to you. The height always depicts the frequency. Make sure that the frequency is plotted against the class mark and not the upper or lower limit of any class.

•Join all the plotted points using a line segment. The curve obtained will be kinked.

•This resulting curve is called the frequency polygon.

2. We will use the following process to draw the frequency curve:

• We will plot the histogram for the data values.

• Then, we will point the midpoints of the class interval on the histogram.

• Now we will join the midpoints using the straight lines.