/*#include<bits/stdc++.h> using namespace std; int main(){ double n,sum=0; int a[1500]; cin>>n; for(int i=1;i<=n;i++){ cin>>a[i]; if(a[i]<=70){ sum+=0.1; }else{ for(int j=1;j<=a[i]/70+1;j++){ sum+=0.1; } } } cout<<sum; return 0; }*/ #include<bits/stdc++.h> using namespace std; int i,j; float ytdx(int x) { float sum = 0.0; if(x%70 == 0){ sum+=1; } else{ sum += x/70+1; } return sum; } int main() { int n,x; float dhfzh=0; cin>>n; for(i=0;i<n;i++) { cin>>x; dhfzh+=ytdx(x); } printf("%.1f",dhfzh/10); return 0; }