공부하자 동진아

def solution(s):
    answer = 0
    if len(s) >= 1 and len(s) <= 5:
        answer = int(s)
    return answer

def solution(n):
    
    x = n ** (1/2)
    
    if x%1 == 0:
        return (x+1) ** 2
        
    return -1

def solution(array, commands):
    
    answer = []
    
    for a in range(len(commands)):
        answer_p = []
        for b in array[commands[a][0]-1:commands[a][1]]:
            answer_p.append(b)
        answer.append(sorted(answer_p)[commands[a][2]-1])
        
    return answer

def solution(array, commands):
    answer = []
    for x in commands:
        first, last, target = x
        answer.append(sorted(array[first-1:last])[target-1])
    return answer

n = int(input())
score = list(map(int, input().split()))
score_change = []

for x in range(n):
    score_change.append(score[x]/max(score)*100)
    
avg = sum(score_change)/n
print(avg)