program AverageThreeDigitNumbers;

var
count, sum, number: integer;
average: real;

begin
count := 0;
sum := 0;

for number := 100 to 999 do
begin
sum := sum + number;
count := count + 1;
end;

average := sum / count;

writeln('Среднее арифметическое трёхзначных чисел: ', average:0:2);

end.