After viewing, text is WAY TO BIG

Hi, I think I know the answer BUT....
When I open the editor and type some text in, the text that goes in is actually quite small, I'd say betweeen 8-10 px.
If I save that and then view the results, the text becomes about 14px. If I view the source of the text, the only thing there is the FCKedtor tags, and in this case, just <p> because I didnt add any formatting.
So why is the text in the after view so much bigger that the text in the editor?

The after view is in a page that has already got a style sheet applied to it, so if the style sheet is affecting the text, how can I over come this (without having to remove the style sheet)?

I thought about putting the text into an iframe on the page, that will exclude the internal style sheet, but wont make good practice for google. Any other suggestions?

Thanks.
P.S Does anyone have any good working examples of FCK editor working. Does your text text get bigger when your viewing it.
Thanks, Graham Vincent
http://sosoduko.com