From a dot plot

The cumulative distribution function shows the proportion of values that are less than or equal to any x-value.

The blue circles above the dot plot are positioned at the data points. Drag them up to form the cumulative distribution function for the data.

 

Using grouped information

Larger data sets are often displayed as histograms. The cumulative proportions can only be exactly determined from the information in a histogram at the class boundaries. However the cumulative distribution function can be sketched by joining these points.

Drag the blue circles to draw the cumulative distribution function for the data set described by the histogram below.

Repeat with a few different data sets.