program ct;
uses crt;
vaar A:array[1..1000] of real;
i,N:integer;
Tb,S:real;
begin clrscr;
write('Nhap so phan tu N: '); readln(N);
for i:=1 to N do
begin
writeln('Nhap phan tu thu ',i,': '); readln(A[i]);
end;
S:=0; Tb:=0;
for i:=1 to N do
if A[i] mod 2=0 then
begin
S:=S+1; Tb:=(Tb+A[i])/S;
end;
writeln('Trung binh cong cac so chan trong day la: ',Tb:4:2);
readln;
end.
Học tốt!