import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.StringTokenizer;
public class Main {
public static void main(String[] args) throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
double[] arr = new double[Integer.parseInt(br.readLine())];
StringTokenizer st = new StringTokenizer(br.readLine(), " ");
br.close();
for (int i = 0; i < arr.length; i++) {
arr[i] = Double.parseDouble(st.nextToken());
}
Arrays.sort(arr);
double sum = 0;
for (double score : arr) {
sum += (score / arr[(arr.length - 1)]) * 100;
}
System.out.println(sum / arr.length);
}
}
언뜻보기에는 복잡해보이지만 무슨 값을 입력하고 계산해야하는지 파악하면 간단한 문제이다.