N=int(eval(input()))

v=list(map(int,input().split()))

v.sort()



ans=v[0]

for i in range(1,N):

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

print(ans)
import sys

input = sys.stdin.readline



def I(): return int(eval(input()))

def MI(): return list(map(int, input().split()))

def LI(): return list(map(int, input().split()))



def main():

    mod=10**9+7

    N=I()

    v=LI()

    v.sort()

    ans=v[0]

    for i in range(1,N):

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

    print(ans)



main()

N = int(eval(input()))
v = list(map(int, input().split()))
v.sort()
ans = v[0]
for i in range(1, N):
    ans = (ans + v[i]) / 2
print(ans)

import sys

input = sys.stdin.readline


def I():
    return int(eval(input()))


def MI():
    return list(map(int, input().split()))


def LI():
    return list(map(int, input().split()))


def main():
    mod = 10**9 + 7
    N = I()
    v = LI()
    v.sort()
    ans = v[0]
    for i in range(1, N):
        ans = (ans + v[i]) / 2
    print(ans)


main()

-N = int(eval(input())) -v = list(map(int, input().split())) -v.sort() -ans = v[0] -for i in range(1, N): -    ans = (ans + v[i]) / 2 -print(ans) +import sys + +input = sys.stdin.readline + + +def I(): +    return int(eval(input())) + + +def MI(): +    return list(map(int, input().split())) + + +def LI(): +    return list(map(int, input().split())) + + +def main(): +    mod = 10**9 + 7 +    N = I() +    v = LI() +    v.sort() +    ans = v[0] +    for i in range(1, N): +        ans = (ans + v[i]) / 2 +    print(ans) + + +main()