Standard emf?

Calculate the standard emf of the following cell at 25°C.





Sn(s) | Sn^2+(aq) || Cu^2+(aq) | Cu(s)





So i know that E(v) for Sn (s) --%26gt; Sn^2+ (aq) + 2e^- is 0.15 and E(v) for Cu^2+ (aq) + 2e^- --%26gt; Cu (s) is 0.16





I have no idea what the equation is to solve this problem, and these electrochemistry problems really make no sense to me at all...some help would be great!

Standard emf?
standard emf = cathode potential - anode potential


potentials are obtained by Nernst's equation