$ sudo apt-get update
$ sudo apt-get install fp-units-rtl 

fp-units-rtl is installed in your system.

Make ensure the fp-units-rtl package were installed using the commands given below,

$ sudo dpkg-query -l | grep fp-units-rtl *

You will get with fp-units-rtl package name, version, architecture and description in a table

fp-units-rtl package basic information: