import java.util.*;
class Main
{
  public static void main(String []args)
  {
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    int z[]=new int[n];
    float c=0.0f;
    for(int i=0;i<n;i++)
    {
      z[i]=sc.nextInt();
    }
    Arrays.sort(z);
    c=z[0];
    for(int i=1;i<n;i++)
    {
      c=(c+z[i])*0.5f;
    }
    System.out.println(c);
  }
} import java.util.*; util.* java class Main
{
  public static void main(String []args)
  {
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    int z[]=new int[n];
    float c=0.0f;
    for(int i=0;i<n;i++)
    {
      z[i]=sc.nextInt();
    }
    Arrays.sort(z);
    c=z[0];
    for(int i=1;i<n;i++)
    {
      c=(c+z[i])*0.5f;
    }
    System.out.println(c);
  }
} Main public static void main(String []args)
  {
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    int z[]=new int[n];
    float c=0.0f;
    for(int i=0;i<n;i++)
    {
      z[i]=sc.nextInt();
    }
    Arrays.sort(z);
    c=z[0];
    for(int i=1;i<n;i++)
    {
      c=(c+z[i])*0.5f;
    }
    System.out.println(c);
  } main {
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    int z[]=new int[n];
    float c=0.0f;
    for(int i=0;i<n;i++)
    {
      z[i]=sc.nextInt();
    }
    Arrays.sort(z);
    c=z[0];
    for(int i=1;i<n;i++)
    {
      c=(c+z[i])*0.5f;
    }
    System.out.println(c);
  } Scanner sc=new Scanner(System.in); sc new Scanner(System.in) int n=sc.nextInt(); n sc.nextInt() sc.nextInt sc int z[]=new int[n]; z new int[n] n float c=0.0f; c 0.0f for(int i=0;i<n;i++)
    {
      z[i]=sc.nextInt();
    } int i=0; int i=0; i 0 i<n i n i++ i++ i {
      z[i]=sc.nextInt();
    } {
      z[i]=sc.nextInt();
    } z[i]=sc.nextInt() z[i] z i sc.nextInt() sc.nextInt sc Arrays.sort(z) Arrays.sort Arrays z c=z[0] c z[0] z 0 for(int i=1;i<n;i++)
    {
      c=(c+z[i])*0.5f;
    } int i=1; int i=1; i 1 i<n i n i++ i++ i {
      c=(c+z[i])*0.5f;
    } {
      c=(c+z[i])*0.5f;
    } c=(c+z[i])*0.5f c (c+z[i])*0.5f (c+z[i]) c z[i] z i 0.5f System.out.println(c) System.out.println System.out System System.out c String []args args
import java.util.*;
class Main
{
  public static void main(String []args)
  {
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    int z[]=new int[n];
    float c=0.0f;
    for(int i=0;i<n;i++)
    {
      z[i]=sc.nextInt();
    }
    Arrays.sort(z);
    c=z[0];
    for(int i=1;i<n;i++)
    {
      c=(c+z[i])*0.5f;
    }
    System.out.println(c);
  }
}