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program bai_giai;
uses crt;
var diem:array[1..50] of real;
    n,i:integer;
    t,dtb:real;
begin
    clrscr;
    write('Nhap so mon: ');  readln(n);
    t:=0;
    for i:=1 to n do
        begin
            write('Nhap so diem mon thu ',i,': ');  readln(diem[i]);
            t:=t+diem[i];
        end;
    dbt:=t/n;
    writeln('Diem trung binh la: ',dtb:0:2);
    if dtb>=8 then write('Gioi')
    else if dtb>=6.5 then write('Kha')
        else if dtb>=5 then write('Trung binh')
            else if dtb>=3.5 then write('Yeu')
                else write('Kem');
    readln;
end.