Need a WordPress Superstar

I am wore out trying to find an answer to this question. I’m really hoping someone can help.

I am using custom post name /%postname%/

In google webmaster tools I have some duplicate content showing under duplicate title tag, and duplicate meta description.

If I look at my top content I see many pages that are showing up twice. For example, I see http://noahsdad.com/story, but further down the page I see http://noahsdad.com/story/.

So is google considering this as different pages? In a browser if I go to a page they seem to all have the ‘/’ however I can take the / off and hit enter and the same page shows up without the /. This isn’t just my site, but I tested this on other people’s sites as well. So I’m assuming either a) this isn’t considered duplicate content, or b.) It is duplicate content and everyone that I tested has duplicate content.

If it isn’t considered duplicate content, is it normal for google webmaster tools to show the two urls (that are really the same url) like I explained?

I know my content has been linked differently all over the web. I’m sure some people link with the slash, and many others link without the slash. Since both links work, I’m wondering if I have two of every page? If that makes sense.

I think I made a mistake (and probably need to cancel all of them) but I did a ton of redirects and redirected as many non / pages as I could to pages that ended in a /. So if you go to http://noahsdad.com/story, it will 301 redirect you to http://noahsdad.com/story/ – Is the wrong way to do it? Should I cancel all of those.