uses crt;
var a:array[1..1000] of real;
n,i,s: real;
begin
clrscr;
writeln('nhap so phan tu cua day so: ');
read(n);
for i:=1 to n do
writeln('a[',i,'] = '); read(a[i]);
s:=0;
for i:=1 to n do
s:=s+a[i];
writeln('gia tri tb cua day la: ',s/n:5);
readln
end.