Math calculations about the speed of a TT..help...

In school I learned that the different parts of a spinning circular object are moving at different speeds depending on how far they are from the center. This is because for a point, lets say half way down a record, to rotate once back to its position it must travel a certain distance ( the diameter up to that point times pi - circumference ) and this distance is different then that of a point at the very edge of the album, or at the begining. The record rotates together though, reaching one revolution at the same time throughout so for this to be possible the different parts would have to travel different speeds. So how do records play at a certain speed ( thirty three and one third etc. ) when acoording to mathematics this is immpossible? How does this work? Also how is the album pressed to take this into consideration? I have just learned this recently so any thing anyone wants correct/ add is greatly appreciated! Thanks for your time!