If no package is available, install from sources
follow procedure described by this post
sudo apt-get update
sudo apt-get install build-essential openssl libreadline6 libreadline6-dev curl git-core zlib1g zlib1g-dev libssl-dev libyaml-dev libsqlite3-dev sqlite3 libxml2-dev libxslt-dev autoconf libc6-dev ncurses-dev automake libtool bison subversion pkg-config libgdbm-dev libffi-dev libreadline-dev
curl -L https://get.rvm.io | bash -s stable
echo 'source ~/.rvm/scripts/rvm' >> ~/.bash_aliases && bashtype rvm | head -n 1and if you get
rvm is a functioninstallation is ok