I forgot that I needed to remove the padding from the larger .entry section, so I did that. I also increased the width of .home-bottom .featuredpost .entry to 230px. Then I added the 40px right padding and although they are now spaced correctly, the images are only 190px wide instead of the required 200px.
If I increase the width of .home-bottom .featuredpost .entry to 240px, the images are correctly sized, but obviously, they won't fit in a row of 3.
Is the designer's math off?