The proportion of waiting times in the sample that are greater than or equal to 18 minutes is 0.16.
<h3>What is a histogram?</h3>
A histogram is used to represent data graphically. The histogram is made up of rectangles whose area is equal to the frequency of the data and whose width is equal to the class interval.
Number of people whose wait time was equal or greater than 18 minutes / total number of people = (2 + 2) / (6 + 7 + 8 + 2 + 2)
4/25 = 0.16
Please find attached an image of a histogram. To learn more about histograms, please check: brainly.com/question/14473126