This is the formula I have tried but it will not work.
=IF(P3=0),"",(AVERAGE(D3,F3,H3,J3,K3,L3,N3)

PS: I don't know what is in P3 (the sum?), but the problem with the above
formula is the parentheses aren't correct. It should be

=IF(P3=0,"",AVERAGE(D3,F3,H3,J3,K3,L3,N3))