uses crt;
var n,i:byte;
a:array[0..100] of real;
tb,min:real;
BEGIN
clrscr;
write('Nhap so phan tu:'); readln(n);
tb:=0;
for i:=1 to n do
begin
write('Nhap a[',i,']:');
readln(a[i]);
tb:=tb+a[i];
end;
tb:=tb/n;
min:=abs(a[1]-tb);
for i:=2 to n do
if abs(a[i]-tb)<min then min:=abs(a[i]-tb);
for i:=1 to n do
if abs(a[i]-tb)=min then break;
write(tb:0:3,' ',a[i]:0:3,' ',i);
readln
END.
Chúc bn hc tốt :>