title: Which ruby version is installed?
body: <p>Sounds strange but I cannot tell which ruby version is installed. If I do</p>
  
  <pre><code>rvm rubies
  </code></pre>
  
  <p>I get</p>
  
  <pre><code>ruby-1.9.2-p180 [ i686 ]
  </code></pre>
  
  <p>but with</p>
  
  <pre><code>ruby -v
  </code></pre>
  
  <p>I get</p>
  
  <pre><code>ruby 1.8.7 (2010-08-16 patchlevel 302) [i686-linux]
  </code></pre>
  
  <p>When trying to</p>
  
  <pre><code>rvm upgrade 1.8.7-p302 1.9.2-p180
  </code></pre>
  
  <p>I get an error</p>
  
  <pre><code>ERROR: Ruby 'ruby-1.8.7-p302' is not installed - please install it first.
  ERROR: Error migrating gems.
  </code></pre>
  
  <p>So, which one is it? 1.8.7-p302 or 1.9.2-p180 ???</p>
  
  <p>Please help me out here! Thanks</p>