import java.util.Arrays;
import java.util.Scanner;

class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int t = scan.nextInt();
        int[] ar = new int[t];
        for (int i = 0; i < t; i++) {
            ar[i] = scan.nextInt();
        }

        Arrays.sort(ar);
        double result = ar[0];
        for (int i = 0; i < ar.length; i++) {
            result = (result+ar[i])/2;
        }

        System.out.println(result);
    }
} import java.util.Arrays; Arrays java.util import java.util.Scanner; Scanner java.util class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int t = scan.nextInt();
        int[] ar = new int[t];
        for (int i = 0; i < t; i++) {
            ar[i] = scan.nextInt();
        }

        Arrays.sort(ar);
        double result = ar[0];
        for (int i = 0; i < ar.length; i++) {
            result = (result+ar[i])/2;
        }

        System.out.println(result);
    }
} Main public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int t = scan.nextInt();
        int[] ar = new int[t];
        for (int i = 0; i < t; i++) {
            ar[i] = scan.nextInt();
        }

        Arrays.sort(ar);
        double result = ar[0];
        for (int i = 0; i < ar.length; i++) {
            result = (result+ar[i])/2;
        }

        System.out.println(result);
    } main {
        Scanner scan = new Scanner(System.in);
        int t = scan.nextInt();
        int[] ar = new int[t];
        for (int i = 0; i < t; i++) {
            ar[i] = scan.nextInt();
        }

        Arrays.sort(ar);
        double result = ar[0];
        for (int i = 0; i < ar.length; i++) {
            result = (result+ar[i])/2;
        }

        System.out.println(result);
    } Scanner scan = new Scanner(System.in); scan new Scanner(System.in) int t = scan.nextInt(); t scan.nextInt() scan.nextInt scan int[] ar = new int[t]; ar new int[t] t for (int i = 0; i < t; i++) {
            ar[i] = scan.nextInt();
        } int i = 0; int i = 0; i 0 i < t i t i++ i++ i {
            ar[i] = scan.nextInt();
        } {
            ar[i] = scan.nextInt();
        } ar[i] = scan.nextInt() ar[i] ar i scan.nextInt() scan.nextInt scan Arrays.sort(ar) Arrays.sort Arrays ar double result = ar[0]; result ar[0] ar 0 for (int i = 0; i < ar.length; i++) {
            result = (result+ar[i])/2;
        } int i = 0; int i = 0; i 0 i < ar.length i ar.length ar ar.length i++ i++ i {
            result = (result+ar[i])/2;
        } {
            result = (result+ar[i])/2;
        } result = (result+ar[i])/2 result (result+ar[i])/2 (result+ar[i]) result ar[i] ar i 2 System.out.println(result) System.out.println System.out System System.out result String[] args args
import java.util.Arrays;
import java.util.Scanner;

class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int t = scan.nextInt();
        int[] ar = new int[t];
        for (int i = 0; i < t; i++) {
            ar[i] = scan.nextInt();
        }

        Arrays.sort(ar);
        double result = ar[0];
        for (int i = 0; i < ar.length; i++) {
            result = (result+ar[i])/2;
        }

        System.out.println(result);
    }
}
