Winter tyres - am I doing it right?

My 07 Mercedes-Benz C-Class estate has slightly different tyres front and back, which is common I am sure.

I have bought four spare alloys fitted with winter tyres which are the same size as the front tyres (205/55 R16 91H), but my present rears are 225/50 R 16?

Will it make nay differance if I fit all four or do I have to buy two different rears?

Asked on 12 December 2011 by roy7066

Answered by Honest John
No. What you plan to do is correct in this circumstance.
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