snow tire size.

[Joel Cohen <joelc@hookup.net>]

To All:

I received a message from the post master that the following message never
got posted.  Come to think of it, I never did get "my copy" of the message
either.  That being said, here comes the questions once again!  As it is now
snowing in Toronto, any and all responses would be apprecated.

The summer tires on my Audi are 205/55/16.  I know that I can get 15 inch
tires around the calipers so the question is.... what is the correct size
winter tire?  I think that it is 195/65/15 but I am not sure.  Any help
would be appreciated!

Also, what is the mathematical formula to determine what size of tires are
equivalent!

TIA,

Joel


P.S. I apologize to anyone who actually received this message the first time!