x5 Spur Gear Sizes

[Chesty]

This might be a daft question but is there an easy way of identifying x5 spur gears once removed from the packet?

For example, does anyone know the diameters of the different size gears...

[super__dan]

102, 106 and 110 are white, 104 and 108 are black.

Write on them what size they are when you take them out of the packet