1.3 Frequency Distribution Tables

Relative Frequency – the number of an event expressed as a fraction of the whole.

Cumulative Frequency – the sum of the frequencies up to and including the event.

Cumulative Relative Frequency – the sum of the relative frequencies up to and including the event.

Ex 1

(a) Calculate the relative frequencies, cumulative frequencies, and cumulative relative frequencies for the data atop page 122. Use the graphing calculators.

(b) Draw a histogram for the data, on the calcs and on paper.

Frequency Polygon

Sometimes instead of drawing a histogram, a frequency polygon is used. To create a frequency polygon, join the midpoints of the intervals with a series of straight lines.

Cumulative Frequency Graph

When drawing a cumulative frequency graph:

• Use a polygon rather than bars
• Join the right endpoints of each interval

(c) Draw a cumulative frequency graph for the data.

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