#coding: UTF-8

import sys
import re
import itertools
from math import log
from collections import deque

### defs ###


### main ###
N = int(sys.stdin.readline())
C = list(map(int, sys.stdin.readline().split()))

sm = sum(C)
ans = len(list(filter(lambda x:x*10<=sm, C))) * 30
print (ans)