Whats the best formula for this?

I am a novice at Excel and need to know what function to use
to average "text" responses in a survey page I've created online.
For example I pose a question of whether or not the individual lives
in a certain county....YES or NO. I'm seeting up spreadsheet to place the averages
of their responses, i.e. YES 60% and NO 40%. I only want the number returned
to the target cell based on their response from another cell
on another worksheet. I know it's probably rather simple
but I've tried the IF, COUNT functions and others but to no evail. Any help from an experienced user
will be appreciated.