Question

O numero dos calçados no EUA é diferente? Explique.

Answer 1

Yes, it's completely distinct from that of Brazil.
There're no algebraic formulae for the conversion between the footwear units in the USA and other countries,  and all you can do is taking a conversion table along with you to a shop, which are prearranged, and make the conversion at once.
At some footwear shops, though, you can have your foot measure taken by the own clerks, without worrying about such conversions