My knowledge of html forms is limited so I can’t speak with authority, but I think that the calculator form in calculate.rhtml.erb needs a submit control or the form never gets submitted.
I verified that a form with one input element only does not need a submit button in my GNU/Linux Firefox browser. But the calculator example has 2 elements, and I needed to add a submit button with the Rails submit_tag method?
Am I overlooking something? Thanks.