title: `File.exist?` won't find file that exists
body: <p>I'm trying to use <code>File.exist?</code> to have a dynamic background. When I try to to point File.exist? to a specific file it doesn't seem to find it.</p>
  
  <pre><code>image_path = "../assets/" + city_code + ".jpg"
  if 
    File.exist?('#{image_path}')
    @image = image_path
  else
    @image = "../assets/coastbanner.jpg"
  end
  </code></pre>
  
  <p>If I remove replace <code>city_code</code> with a path that I know exists, it still won't find it. I must bee missing something small.</p>
  
  <p>I wanted to be a little more clear:  If I remove the interpolation/variable and replace it with a path that I know works, '../assets/coastbanner.jpg' for example, it still will not work.  In fact, no valid path seems to get it to yield a true response. </p>