[Qgis-user] how to install qgis 1.8 instead 1.75 on ubunto

[Milton Cezar Ribeiro]

 Dear all;

I have some machines with Ubuntu, and sometimes when I install QGIS I
get version 1.8, other times version 1.75 are installed.

Why this occurs? How can I garantee that v1.8 come to be always installed?

Cheers

milton