#import pysnooper

import os,re,sys,operator,math,heapq,string

from collections import Counter,deque

from operator import itemgetter

from itertools import accumulate,combinations,groupby

from sys import stdin,setrecursionlimit

from copy import deepcopy



setrecursionlimit(10**6)



n=int(stdin.readline().rstrip())

v=sorted([int(i) for i in stdin.readline().rstrip().split()])

now=(v[0]+v[1])/2

for i in range(2,n):

    now=(now+v[i])/2

print(now)
#import pysnooper

#import os,re,sys,operator,math,heapq,string

#from collections import Counter,deque

#from operator import itemgetter

#from itertools import accumulate,combinations,groupby,combinations_with_replacement

from sys import stdin,setrecursionlimit

#from copy import deepcopy



setrecursionlimit(10**6)

input=stdin.readline



n=int(eval(input()))

a=sorted([int(i) for i in input().split()])

ans=(a[0]+a[1])/2

for i in range(2,n):

    ans=(ans+a[i])/2

print(ans)
# import pysnooper
import os, re, sys, operator, math, heapq, string
from collections import Counter, deque
from operator import itemgetter
from itertools import accumulate, combinations, groupby
from sys import stdin, setrecursionlimit
from copy import deepcopy

setrecursionlimit(10**6)
n = int(stdin.readline().rstrip())
v = sorted([int(i) for i in stdin.readline().rstrip().split()])
now = (v[0] + v[1]) / 2
for i in range(2, n):
    now = (now + v[i]) / 2
print(now)

# import pysnooper
# import os,re,sys,operator,math,heapq,string
# from collections import Counter,deque
# from operator import itemgetter
# from itertools import accumulate,combinations,groupby,combinations_with_replacement
from sys import stdin, setrecursionlimit

# from copy import deepcopy
setrecursionlimit(10**6)
input = stdin.readline
n = int(eval(input()))
a = sorted([int(i) for i in input().split()])
ans = (a[0] + a[1]) / 2
for i in range(2, n):
    ans = (ans + a[i]) / 2
print(ans)

-import os, re, sys, operator, math, heapq, string -from collections import Counter, deque -from operator import itemgetter -from itertools import accumulate, combinations, groupby +# import os,re,sys,operator,math,heapq,string +# from collections import Counter,deque +# from operator import itemgetter +# from itertools import accumulate,combinations,groupby,combinations_with_replacement -from copy import deepcopy +# from copy import deepcopy -n = int(stdin.readline().rstrip()) -v = sorted([int(i) for i in stdin.readline().rstrip().split()]) -now = (v[0] + v[1]) / 2 +input = stdin.readline +n = int(eval(input())) +a = sorted([int(i) for i in input().split()]) +ans = (a[0] + a[1]) / 2 -    now = (now + v[i]) / 2 -print(now) +    ans = (ans + a[i]) / 2 +print(ans)