difference between tire sizes?

[SkidmarkSS]

What is the difference between a 325/50/15 and 28.10 or 29.10? I am being told the size difference is very minimal.

 

[StreetBu]

For starters it's only 27.9" tall and the section width is 13" lets see if this works

http://www.tirerack.com/tires/Spec.jsp?make=BFGoodrich&model=g-Force+T%2FA+Drag+Radial+2&partnum=325R5GTADR&vehicleSearch=false&fromCompare1=yes&place=0