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

public class Main {

    public static void main(String args[]) {

        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        Integer[] v = new Integer[n];
        for (int i = 0; i < n; i++) {
            v[i] = sc.nextInt();
        }

        Arrays.sort(v);
        double result = v[0];
        for (int i = 1; i < n; i++) {
            result = (result + v[i]) / 2.0;
        }

        System.out.println(result);
    }
} import java.util.Arrays; Arrays java.util import java.util.Scanner; Scanner java.util public class Main {

    public static void main(String args[]) {

        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        Integer[] v = new Integer[n];
        for (int i = 0; i < n; i++) {
            v[i] = sc.nextInt();
        }

        Arrays.sort(v);
        double result = v[0];
        for (int i = 1; i < n; i++) {
            result = (result + v[i]) / 2.0;
        }

        System.out.println(result);
    }
} Main public static void main(String args[]) {

        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        Integer[] v = new Integer[n];
        for (int i = 0; i < n; i++) {
            v[i] = sc.nextInt();
        }

        Arrays.sort(v);
        double result = v[0];
        for (int i = 1; i < n; i++) {
            result = (result + v[i]) / 2.0;
        }

        System.out.println(result);
    } main {

        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        Integer[] v = new Integer[n];
        for (int i = 0; i < n; i++) {
            v[i] = sc.nextInt();
        }

        Arrays.sort(v);
        double result = v[0];
        for (int i = 1; i < n; i++) {
            result = (result + v[i]) / 2.0;
        }

        System.out.println(result);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc Integer[] v = new Integer[n]; v new Integer[n] n for (int i = 0; i < n; i++) {
            v[i] = sc.nextInt();
        } int i = 0; int i = 0; i 0 i < n i n i++ i++ i {
            v[i] = sc.nextInt();
        } {
            v[i] = sc.nextInt();
        } v[i] = sc.nextInt() v[i] v i sc.nextInt() sc.nextInt sc Arrays.sort(v) Arrays.sort Arrays v double result = v[0]; result v[0] v 0 for (int i = 1; i < n; i++) {
            result = (result + v[i]) / 2.0;
        } int i = 1; int i = 1; i 1 i < n i n i++ i++ i {
            result = (result + v[i]) / 2.0;
        } {
            result = (result + v[i]) / 2.0;
        } result = (result + v[i]) / 2.0 result (result + v[i]) / 2.0 (result + v[i]) result v[i] v i 2.0 System.out.println(result) System.out.println System.out System System.out result String args[] args public class Main {

    public static void main(String args[]) {

        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        Integer[] v = new Integer[n];
        for (int i = 0; i < n; i++) {
            v[i] = sc.nextInt();
        }

        Arrays.sort(v);
        double result = v[0];
        for (int i = 1; i < n; i++) {
            result = (result + v[i]) / 2.0;
        }

        System.out.println(result);
    }
} public class Main {

    public static void main(String args[]) {

        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        Integer[] v = new Integer[n];
        for (int i = 0; i < n; i++) {
            v[i] = sc.nextInt();
        }

        Arrays.sort(v);
        double result = v[0];
        for (int i = 1; i < n; i++) {
            result = (result + v[i]) / 2.0;
        }

        System.out.println(result);
    }
} Main
import java.util.Arrays;
import java.util.Scanner;

public class Main {

    public static void main(String args[]) {

        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        Integer[] v = new Integer[n];
        for (int i = 0; i < n; i++) {
            v[i] = sc.nextInt();
        }

        Arrays.sort(v);
        double result = v[0];
        for (int i = 1; i < n; i++) {
            result = (result + v[i]) / 2.0;
        }

        System.out.println(result);
    }
}
