#include <stdio.h> int calc(int x) { if(x%70==0) return x/70; else return x/70+1; } int main() { int i,n,a; double sum=0; scanf("%d",&n); for(i=1;i<=n;i++) { scanf("%d",&a); sum+=calc(a); } printf("%.1lf\n",sum/10.0); return 0; }