Answer:
The running time of episode 15 commercials is 22.5 minutes
Explanation:
The running time in minutes of the tv episode is given by : 30-0.5c
Where c is the number of commercials aired during the episode.
Now we are supposed to find the running time of episode 15 commercials
Substitute c = 15
The running time in minutes of the tv episode =30-0.5c
The running time of episode 15 commercials=30-0.5(15)=22.5
Hence the running time of episode 15 commercials is 22.5 minutes