Hi all can anyone help? Just had my 2010 Mondeo serviced and told I needed 2 new tyres which I said I would sort out myself . Went onto websites inputted my reg which said my tyres should be 235/45/17 thought I'd check my car tyres just to be safe but they are 225/50/17 just purchased car recently I'm thinking I've got wrong tyres fitted and I've noticed the wear is mainly on outside of tyre

They're pretty much the same size tyre within a mm or so, just slightly different on the profiles. If the wear is on the outside it may be a tracking issue and will need fixing when the new tyres are picked up.

The wheels may have been replaced by its former owner. When the car left the factory it will have had the tyre size on that you see on the websites, however, it could be that the previous owner changed the wheels slightly, or as Paul said, just put different tyres on with a different profile.