Target age (Target audience)

Initially i wanted to make my target audience for all ages but thinking back it is hard to please everyone, it is like featuring a colour-in picture and local business advertising in the same magazine and they both target different ages. My magazines target age will be 18 to 24 year olds because i believe it is essential for this age group to learn more about your city which will help know more about what they want for future and what this city offers for them