Inconsistent image alignment

I am working after someone else using a heavily customized Skeleton theme. Image alignment code align=center occurs in page.php. The problem is that the image (Request an Appt image with link) centers fine on some pages, but not on others, including this page. I’ve tried several things, including clearing before and after code and trying a float right (which fixed the problem on the bad pages, but messed up the good pages).
Any ideas?