import java.util.Scanner;
import java.util.Arrays;
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int Num = sc.nextInt();
float[] arr = new float[Num];
float[] arr1 = new float[Num];
float Max;
double Sum=0;
if(Num<=1000) {
for(int i=0;i<Num;i++) {
arr[i] = sc.nextInt();
if(i==Num-1) {
Arrays.sort(arr);
Max = arr[Num-1];
for(int j=0;j<Num;j++) {
arr1[j] = arr[j]/Max*100;
Sum+=arr1[j];
if(j==Num-1) {
System.out.format("%.2f%n", Sum/Num);
}
}
}
}
}
}
}