Spreading 4 images equally across 100 percent of div

Hi

I'm looking for a solution to spread 4 images equally across a responsive webpage -- 100 percent

Right now I"m using padding right and left, and I know that's not the way to go.

I think the culprit is this div:  div#muse-images

Here's the link to the page, work in progress  Website

You see two rows of images, 4 across.  I want the images to be spread equally horizontally across the page.  I also want to get rid of the temporary 10 pixel padding right and left of each image.  It was just there for this initial mockup.

I may need to all some overall margin right and left to align it a bit, but that is not the main issue.

Thanks for any help,

Rowby