Var
mean, count, n: real;
i: byte;
begin
mean := 0;
count := 0;
for i := 1 to 10 do
begin
readln(n);
if (( n <= 18 ) and ( n >=-5 )) then
begin
mean := mean + n;
count := count + 1;
end;
end;
mean := mean / count;
writeln('Среднее арифметическое = ', mean);
end.