Updating attributes from check_box - ruby-on-rails

Question

I'm using nested models in my first Ruby on Rails app and now I've run into a problem. I have a Survey model that has_many :questions which in turn belongs_to :survey and the model Question has_many :answers. My Answer model then belongs_to :question.
Now I want to update a boolean attribute :guess within my :answers controller. To this end I've created a new action :quiz_guess which looks like this:
def quiz_guess
Answer.update(params[:id], guess: false)
puts("Guess saved")
redirect_to(:action => 'show', :id => #survey.next, :survey_id => #survey.id)
end
my view looks like this:
<%= form_tag quiz_guess_questions_path, :method => :put do %>
<% for question in #survey.questions do %>
<li><%= h question.content %></li>
<% for answer in question.answers do %>
<li><%= h answer.content %>
<%= form_for :guess do |f| %>
<%= f.check_box(:guess, :method => :put) %>
<% end %>
</li>
<% end %>
<% end %>
<% end %>
Obviously I've read the documentation, as well as this blog post, but I don't understand how to implement it in my controller and view.
With this code I'm not able to update the correct :guess attribute but rather I update a different one (with a different :id). Can anybody shed some light as to what I do wrong?

Answer 1

I ended up looking at this Railscast where Ryan Bates shows how to update multiple attributes with fields_for. This is my new view:
<%= form_tag quiz_guess_questions_path, :method => :put do %>
<% for question in #survey.questions do %>
<li><%= question.content %></li>
<% for answer in question.answers do %>
<li>
<%= fields_for "answers[]", answer do |f| %>
<%= answer.content %>
<%= f.check_box :guess %>
<% end %>
</li>
<% end %>
<% end %>
<%= submit_tag "Guess" %>
<% end %>
and my new controller:
def quiz_guess
Answer.update(params[:answers].keys, params[:answers].values)
flash[:notice] = "Guess saved successfully."
redirect_to questions_url
end