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HI EVERYONE JUST BOUGHT MYSELF A C220CDI ESTATE AVANTGARDE ON 56 PLATE. THE TWO FRONT TYRES ARE 224/45V17 AND THE TWO REAR ARE 245/40V17 THE FRONT TYRES ARE LESS EXPENSIVE THAN THE REAR. IS THIS CORRECT. A FIRST FOR ME TO HAVE CAR WITH TWO DIFFERENT SIZED TYRES. OBVIOUSLY I ONLY HAVE ONE...