Finding an Estimate for Interquartile Range

The video tutorial explains how to use a cumulative frequency graph to estimate the interquartile range and analyze film lengths. It covers calculating the interquartile range by identifying upper and lower quartiles and determining the percentage of films over 120 minutes. The tutorial also includes verifying a claim about the percentage of films exceeding a certain length.

What is the total number of films represented in the cumulative frequency graph?

What percentage of films are over 120 minutes long, and how did you calculate it?

Describe how to determine the number of films that are over 120 minutes long using the graph.