<p>You've completed <%= @completed.length %> out of <%= @questions.length %> questions.</p>
<div class="progress"><div class="determinate" style="width: <%= (@completed.length / (@questions.length.to_f)) * 100 %>%"></div></div>
<% @questions.each do |question| %>
  <p><a href="/questions/<%= question.id %>"><%= question.text %></a> <% if @completed.include?(question.id) %><img src="/done.png"><% end %></p>
<% end %>

<p>You've completed <%= @completed ? @completed.length : 0 %> out of <%= @questions.length %> questions.</p>
<div class="progress"><div class="determinate" <% if @completed %>style="width: <%= (@completed.length / (@questions.length.to_f)) * 100 %>%"<% end %>></div></div>
<% @questions.each do |question| %>
  <p><a href="/questions/<%= question.id %>"><%= question.text %></a> <% if @completed and @completed.include?(question.id) %><img src="/done.png"><% end %></p>
<% end %>

Fix display for people who don't have a session yet
Fix display for people who don't have a session yet
