InfoPath Dev

I figured out how to make things work for me. Thanks for reading my post.

I am very new to creating InfoPath forms. I have a general understanding of functions and forms but I am stumped about a CountIf funciton. I have a form with two sections A and B within each section there are 5 questions that can be answered with M, N, or U. How would I go about setting a rule or condition on another box that will add each M or ...