program ct;
uses crt;
var i,n,s:integer; tbc:real;
A:array[1..100] of integer;
begin
clrscr;
write('nhap so mon n:=');readln(n);
for i:=1 to n do
begin
write('nhap diem A[',i,']:=');readln(A[i]);
end;
s:=0;
for i:=1 to n do
begin
s:=s+A[i];
tbc:=s/n;
end;
writeln('trung bonh cong la:',tbc:10:2);
readln
end.