This might sound silly. But in this day and age, is it appropriate for a guy in his 20s to approach a girl in public to ask for her number?

I'd love to hear everybodys take on this post. I'm a guy in my 20s. I find i'm so limited to meet girls, and its frustrating at times when you feel you have no control over your dating life. So is it appropriate for a guy to approach a girl in hopes to get her number to get to know her and take her out on a date?