I think age is important on a place work. I mean: there are some workplaces where age means nothing, other where it's the first thing. It depends.
And not only real age, but how you "look" too: is not that the first thing for most of people?
I can take myself as example. My work is teaching about software's stuff, programs etc. - and when I teach, most of times it is for business working people. For this reason, they can be from 25 to 60 years old. I have never had problems, people always think I'm younger than I am...I mean like 22-23. And it's ok. But some of them believe that when you are 22 you cannot be competent, qualified.
The nice thing is that many people feel relaxed when they see me on a course. "Oh wow! You are the teacher? Well, I have no fears more...", and they feel so when I have to test them for an exam too. That's why they always expect for "terror" teacher, like in high-school...hehe, it's so funny. Anyway they learn, pass their tests and finally they always give me some gifts 
There was just one time where I had problems. Some months ago my firm sent me to teach in a high-school...oh man, it was an experience...I had 2 classes for 2 hours. Guys were all 16-17 years old.
It was a tragedy. When they saw me first time, they thought I was some teacher's daughter...but when I told them I was their teacher for Internet Network, they began to ask me thousand questions: "Oh Really?? But you're a couple years older than me! It is not possible!!". I told them I was not 20, but it had no effects...they felt me like "one of them", so began to treat me like a school friend...Consequences were no concentration, no working, no learning! Just they called my name thousand times (no "teacher"! lol). I could not be angry, cause they were so nice...but I realized I could not stay in those classes. They needed a more "authority" person...and I looked too young!
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