title: Where to put mathematical calculations in Rails?
body: <p><em>In case you were unaware, this is a beginner's question.</em></p>
  
  <p>Having learned a bit of Ruby, I have ventured onto Rails, but have run into a brick wall when it comes to organizing methods. I'm building something which is supposed to take the data/parameters you get when someone creates something, but instead of showing it like you would a tweet or blog post, I want to use them as variables in some mathematical calculations, the results of which I <em>then</em> want to show.</p>
  
  <p>Now, in Ruby, I would make a method for each little math operation, to make sure they (the methods) have a single responsibility each. In Rails, though, what am I supposed to do? In case you don't understand my problem, I think it has to do with my lack of understanding of instances in Rails. Instances in Ruby can call upon the methods I make, but <em>where do I call upon my methods (actions?) in Rails?</em></p>