The durations of a random sample of 16 commercials are below (in seconds). find the mean, median, and mode of these durations. 30, 12, 26, 7, 14, 35, 20, 30, 55, 8, 35, 18, 42, 15, 30, 10

First arrange in ascending order of time:-

7, 8, 10, 12, 14, 15, 18, 20, 26, 30, 30, 30, 35, 35, 42, 55

MOde is the value occuring mos  = 30.

Median is the mean of 2 middle numbers = (20 + 26) / 2 = 23

Mean = sum of the 16 numbers  / 16  =  387/16  = 24.2