#include<algorithm>

#include<cmath>

#include<cstdio>

#include<iostream>

using namespace std;

int main(){

int n;

cin>>n;

double time=0;

const double v=50.0,u=1.0,d=.5;

for(int i=1;i<=n;i++){

double x,y,p;

cin>>x>>y>>p;

double dis=sqrt(x*x+y*y);

time+=2*dis/v+p*(u+d);

}

cout<<ceil(time);

return 0;

}