convert lat/longs

Hey guys. I have a little problem I've been trying to wrap my head around. I'm not an excel expert, so I thought I'd come look for some help. I'm trying to create a spreadsheet that will convert coordinates from DDMMSS.00 to DDMM.000. I found another thread that discusses this same issue, but I was unable to make it work for me. I'm attaching a sample spreadsheet that basically shows what I'm trying to do. Let me know if there's any more info ya'll need.

Chris