Decrease Padding Around Images In Posts

I have searched the forum, but am having no luck finding the right search terms to search to find an answer to this. Or if i found something I thought would work — it didn’t.

I am using the Twenty Eleven Theme, and I have created a child theme and am working off that.

I would like to decrease the padding around images I use in articles/posts. I assume I have to change a few things, because I use left align, right align etc…. for images.

My brain is about fried, trying to figure this out, so any help would be greatly appreciated.

Thanks,
Cathie