How do you make a formula rule for a column in excel to get different answers for each row?

I am making a book for my coworkers that will do the work for them so they will stop complaining. What I am trying to do is instruct Excel to sum 3 cells from each row and show the total in a certain cell. In other words I want the answer to the sum of A2 C2 and D2 to appear in F2, and A3 C3 and D3 to appear in F3 without entering the formula in each cell. Is this possible and how do you do it?