#include <bits/stdc++.h>
using namespace std;
using lint = long long;
const lint mod = 1e9 + 7;
#define all(x) (x).begin(), (x).end()
#define bitcount(n) __builtin_popcountl((lint)(n))
#define fcout cout << fixed << setprecision(15)
#define highest(x) (63 - __builtin_clzl(x))
template<class T> inline void YES(T condition){ if(condition) cout << "YES" << endl; else cout << "NO" << endl; }
template<class T> inline void Yes(T condition){ if(condition) cout << "Yes" << endl; else cout << "No" << endl; }
template<class T = string, class U = char>int character_count(T text, U character){ int ans = 0; for(U i: text){ ans += (i == character); } return ans; }
lint power(lint base, lint exponent, lint module){ if(exponent % 2){ return power(base, exponent - 1, module) * base % module; }else if(exponent){ lint root_ans = power(base, exponent / 2, module); return root_ans * root_ans % module; }else{ return 1; }}
struct position{ int y, x; }; position mv[4] = {{0, -1}, {1, 0}, {0, 1}, {-1, 0}}; // double euclidean(position first, position second){ return sqrt((second.x - first.x) * (second.x - first.x) + (second.y - first.y) * (second.y - first.y)); }
template<class T, class U> string to_string(pair<T, U> x){ return to_string(x.first) + "," + to_string(x.second); } string to_string(string x){ return x; }
template<class itr> void array_output(itr start, itr goal){ string ans; for(auto i = start; i != goal; i++) ans += to_string(*i) + " "; if(!ans.empty()) ans.pop_back(); cout << ans << endl; }
template<class itr> void cins(itr first, itr last){ for(auto i = first; i != last; i++){ cin >> (*i); } }
template<class T> T gcd(T a, T b){ if(a && b){ return gcd(min(a, b), max(a, b) % min(a, b)); }else{ return a; }} template<class T> T lcm(T a, T b){ return a / gcd(a, b) * b; }
struct combination{ vector<lint> fact, inv; combination(int sz) : fact(sz + 1), inv(sz + 1){ fact[0] = 1; for(int i = 1; i <= sz; i++){ fact[i] = fact[i - 1] * i % mod; } inv[sz] = power(fact[sz], mod - 2, mod); for(int i = sz - 1; i >= 0; i--){ inv[i] = inv[i + 1] * (i + 1) % mod; } } lint C(int p, int q) const{ if(q < 0 || p < q) return 0; return (fact[p] * inv[q] % mod * inv[p - q] % mod); } };
template<class itr> bool next_sequence(itr first, itr last, int max_bound){ itr now = last; while(now != first){ now--; (*now)++; if((*now) == max_bound){ (*now) = 0; }else{ return true; } } return false; }

double eps = 1e-6;

pair<pair<double, double>, pair<double, double>> circle_intersection(double x1, double y1, double r1, double x2, double y2, double r2){
    double x = x2 - x1, y = y2 - y1;
    double ab = x * x + y * y;
    double a = (ab + r1 * r1 - r2 * r2) / 2;
    double root = ab * r1 * r1 - a * a;
    if(root < -eps){
        return {{1e9, 1e9}, {1e9, 1e9}};
    }else if(root < 0){
        root = 0;
    }
    root = sqrt(root);
    pair<double, double> ret1 = {(a * x + y * root) / ab + x1, (a * y - x * root) / ab + y1};
    pair<double, double> ret2 = {(a * x - y * root) / ab + x1, (a * y + x * root) / ab + y1};
    return {ret1, ret2};
}

double euclid_distance(double x1, double y1, double x2, double y2){
    double x = x2 - x1, y = y2 - y1;
    return sqrt(x * x + y * y);
}

int main(){
    int N, K;
    cin >> N >> K;
    double x[N], y[N], c[N];
    for(int i = 0; i < N; i++){
        cin >> x[i] >> y[i] >> c[i];
    }
    double low = 0, high = 1e9;
    for(int _ = 0; _ < 100; _++){
        double mid = (low + high) / 2;
        vector<pair<double, double>> intersections;
        for(int i = 0; i < N; i++){
            for(int j = i + 1; j < N; j++){
                auto intersection = circle_intersection(x[i], y[i], mid / c[i], x[j], y[j], mid / c[j]);
                if(intersection.first.first < 1e9 - 100){
                    intersections.push_back(intersection.first);
                    intersections.push_back(intersection.second);
                }
            }
            intersections.push_back({x[i], y[i] + mid / c[i]});
        }
        bool is_ok = false;
        for(auto i: intersections){
            int near = 0;
            for(int j = 0; j < N; j++){
                near += (euclid_distance(i.first, i.second, x[j], y[j]) * c[j] < mid + eps);
            }
            if(near >= K){
                is_ok = true;
            }
        }
        if(is_ok){
            high = mid;
        }else{
            low = mid;
        }
    }
    fcout << low << endl;
}


Measured memory_bytes: 256