When something states 6 through 18, what does that mean?

Question

would it mean 6 UP TO the age of 18 or would it indicate 6 to the age of 18 years, 11 months and 30 days...(which would really mean 6 UP TO the age of 19)?????

What do you guys think and FYI this info is regarding a youth bus pass fare

This is the site if you want to see what i am referring to in its original context>>scroll down to "Youth Regional Monthly Pass"

http://www.sdmts.com/fares.asp

Answer 1

It means once you reach the age of 18 it no longer applies!

Answer 2

I would say that 18-year-olds are eligible.  You are eligible until your 19th birthday.

Answer 3

From the time you turn 6 until you turn 19. "Through 18" means including your 18th year.

"UP TO the age of 18" means just that; once you turn 18, you're not eligible.