#include<iostream>
#include<vector>

#define REP(i,n) for(i=0; i<n; i++)
using namespace std;

int main()
{
    int n;
    cin>>n;
    vector<int> v;
    int i,votes,standard=0;
    REP(i,n) {
        cin>>votes;
        v.push_back(votes);
        standard+=votes;
    }
    standard/=10;
    int cnt=0;
    REP(i,v.size()) {
        if(v[i]<=standard) { cnt++; }
        else{}
    }
    cout << cnt*30 << endl;
    return 0;
}