#include <bits/stdc++.h>
using namespace std;
double a[7],b[7],c[7],t;
int dem,i;
int main()
{
for (i=1; i<=7; i++) cin>>a[i]>>b[i];
for (i=1; i<=7; i++) c[i]=(a[i]+b[i])/2;
t=0;
dem=0;
for (i=1; i<=7; i++)
{
t+=c[i];
if (c[i]<10) dem++;
}
cout<<"Nhiet do trung binh la: "<<fixed<<setprecision(2)<<t/(7*1.0)<<endl;
cout<<"So ngay nhiet do trung binh nho hon 10 do la: "<<dem;
return 0;
}