[lmikle]

Код:

var 
  i: integer;
  summ: array[1..25] of  real;
begin
  for i:=1 to 25 do
       begin
         If (SG2.Cells[2,i] = '') Or (SG3.Cells[8,i] = '') Or (SG3.Cells[14,i] = '') Or (SG3.Cells[20,i] = '') Then  SG3.Cells[26,i]:= '0' Else
       begin
         summ:=(StrToFloat(SG3.Cells[2,i])+ StrToFloat(SG3.Cells[8,i])+                     
                       StrToFloat(SG3.Cells[14,i])+ StrToFloat(SG3.Cells[20,i])/4;
         SG3.Cells[26,i]:=FloatToStr(summ,ffFixed,1,1);
       End;
       end;
end;