#include<bits/stdc++.h> using namespace std; int main(){ int a,k=0; cin>>a; int b[a]={0}; for(int i=0;i<a;i++){ cin>>b[i]; if(b[i]>70){ if(b[i]%70==0){ k += b[i]/70; }else if(b[i]%70!=0){ k+=b[i]/70+1; } } else if(b[i]<=70){ k++; } } printf("%.1lf",k*1.0/10); return 0; }