title: Ruby - Install Sinatra gem error on ruby mine
body: <p>I'm working on a new project in Ruby, which I'm learning, and I need to install Sinatra gem and I'm getting the following error: </p>
  
  <blockquote>
    <p>"Following gems were not installed: sinatra-sinatra (0.10.1):  While
    executing gem ... (Gem::UnsatisfiableDependencyError)
         Unable to resolve dependency: 'sinatra-sinatra (= 0.10.1)' requires 'rack (>= 1.0)'"</p>
  </blockquote>
  
  <p>Currently I'm using, RubyMine (Windows). Any help would be appreciated.</p>
  
  <p>Thanks</p>