
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();
		int[] V = new int[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;
		}

		System.out.print(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();
		int[] V = new int[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;
		}

		System.out.print(result);

	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int[] V = new int[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;
		}

		System.out.print(result);

	} main {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int[] V = new int[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;
		}

		System.out.print(result);

	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int N = sc.nextInt(); N sc.nextInt() sc.nextInt sc int[] V = new int[N]; V new int[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;
		} int i = 1; int i = 1; i 1 i < N i N i++ i++ i {
			result = (result + V[i]) / 2;
		} {
			result = (result + V[i]) / 2;
		} result = (result + V[i]) / 2 result (result + V[i]) / 2 (result + V[i]) result V[i] V i 2 System.out.print(result) System.out.print 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();
		int[] V = new int[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;
		}

		System.out.print(result);

	}
} public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int[] V = new int[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;
		}

		System.out.print(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();
		int[] V = new int[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;
		}

		System.out.print(result);

	}
}
