import java.util.*;

public class Main{

  public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int[] data = new int[n];

    for(int i = 0;i < data.length;i++) data[i] = sc.nextInt();

    Arrays.sort(data);

    double sum = data[0];

    for(int i = 1;i < n;i++){
      sum += data[i];
      sum /= 2;
    }

    System.out.println(sum);

  }

} import java.util.*; util.* java public class Main{

  public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int[] data = new int[n];

    for(int i = 0;i < data.length;i++) data[i] = sc.nextInt();

    Arrays.sort(data);

    double sum = data[0];

    for(int i = 1;i < n;i++){
      sum += data[i];
      sum /= 2;
    }

    System.out.println(sum);

  }

} Main public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int[] data = new int[n];

    for(int i = 0;i < data.length;i++) data[i] = sc.nextInt();

    Arrays.sort(data);

    double sum = data[0];

    for(int i = 1;i < n;i++){
      sum += data[i];
      sum /= 2;
    }

    System.out.println(sum);

  } main {

    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int[] data = new int[n];

    for(int i = 0;i < data.length;i++) data[i] = sc.nextInt();

    Arrays.sort(data);

    double sum = data[0];

    for(int i = 1;i < n;i++){
      sum += data[i];
      sum /= 2;
    }

    System.out.println(sum);

  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int[] data = new int[n]; data new int[n] n for(int i = 0;i < data.length;i++) data[i] = sc.nextInt(); int i = 0; int i = 0; i 0 i < data.length i data.length data data.length i++ i++ i data[i] = sc.nextInt(); data[i] = sc.nextInt() data[i] data i sc.nextInt() sc.nextInt sc Arrays.sort(data) Arrays.sort Arrays data double sum = data[0]; sum data[0] data 0 for(int i = 1;i < n;i++){
      sum += data[i];
      sum /= 2;
    } int i = 1; int i = 1; i 1 i < n i n i++ i++ i {
      sum += data[i];
      sum /= 2;
    } {
      sum += data[i];
      sum /= 2;
    } sum += data[i] sum data[i] data i sum /= 2 sum 2 System.out.println(sum) System.out.println System.out System System.out sum String[] args args public class Main{

  public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int[] data = new int[n];

    for(int i = 0;i < data.length;i++) data[i] = sc.nextInt();

    Arrays.sort(data);

    double sum = data[0];

    for(int i = 1;i < n;i++){
      sum += data[i];
      sum /= 2;
    }

    System.out.println(sum);

  }

} public class Main{

  public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int[] data = new int[n];

    for(int i = 0;i < data.length;i++) data[i] = sc.nextInt();

    Arrays.sort(data);

    double sum = data[0];

    for(int i = 1;i < n;i++){
      sum += data[i];
      sum /= 2;
    }

    System.out.println(sum);

  }

} Main
import java.util.*;

public class Main{

  public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int[] data = new int[n];

    for(int i = 0;i < data.length;i++) data[i] = sc.nextInt();

    Arrays.sort(data);

    double sum = data[0];

    for(int i = 1;i < n;i++){
      sum += data[i];
      sum /= 2;
    }

    System.out.println(sum);

  }

}
