#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#define _SILENCE_CXX17_RESULT_OF_DEPRECATION_WARNING
#include "bits/stdc++.h"
#define rep(i, n) for(int i=0; i<(n); ++i)
#define FOR(i, m, n) for(int i=(m); i<(n); ++i)
#define rrep(i, n) for(int i=(n)-1; i>=0; --i)
#define rfor(i, m, n) for(int i=(m); i>=(n); --i)
#define sz(x) ((int)(x).size())
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
#define range_it(a, l, r) (a).begin() + (l), (a).begin() + (r)

using namespace std;
using LL = long long;		using ld = long double;
using VB = vector<bool>;	using VVB = vector<VB>;
using VI = vector<int>;		using VVI = vector<VI>;
using VL = vector<LL>;		using VVL = vector<VL>;
using VS = vector<string>;	using VD = vector<double>;
using PII = pair<int, int>;	using VP = vector<PII>;
using PLL = pair<LL, LL>;	using VPL = vector<PLL>;
template<class T>using Grid = vector<vector<T>>;
template<class T>using PQ = priority_queue<T>;
template<class T>using PQS = priority_queue<T, vector<T>, greater<T>>;
constexpr int inf = (int)1e9;
constexpr LL inf_ll = (LL)1e6, MOD = 1000000007;
constexpr ld PI = M_PI, EPS = 1e-12;

template<class T>inline void Sort(T& a)noexcept { sort(all(a)); }
template<class T>inline void RSort(T& a)noexcept { sort(rall(a)); }
template<class T>inline void Reverse(T& a)noexcept { reverse(all(a)); }
template<class T>inline void Unique(T& a)noexcept { a.erase(unique(all(a)), a.end()); }
template<class T>inline T Sorted(T a)noexcept { Sort(a); return a; }
template<class T>inline T RSorted(T a)noexcept { RSort(a); return a; }
template<class T>inline T Reversed(T a)noexcept { Reverse(a); return a; }
template<class T>inline T Uniqued(T a)noexcept { Unique(a); return a; }
template<class T>inline auto Max(const T& a)noexcept { return *max_element(all(a)); }
template<class T>inline auto Min(const T& a)noexcept { return *min_element(all(a)); }
template<class T>inline int MaxPos(const T& a)noexcept { return max_element(all(a)) - a.begin(); }
template<class T>inline int MinPos(const T& a)noexcept { return min_element(all(a)) - a.begin(); }
template<class T, class U>inline int Count(const T& a, const  U& v)noexcept { return count(all(a), v); }
template<class T, class U>inline int Find(const T& a, const U& v)noexcept { auto pos = find(all(a), v); return pos == a.end() ? -1 : pos - a.begin(); }
template<class T, class U>inline U Sum(const T& a, const U& v)noexcept { return accumulate(all(a), v); }
template<class T, class U>inline int Lower(const T& a, const U& v)noexcept { return lower_bound(all(a), v) - a.begin(); }
template<class T, class U>inline int Upper(const T& a, const U& v)noexcept { return upper_bound(all(a), v) - a.begin(); }
template<class T, class P>inline void RemoveIf(T& a, P f)noexcept { a.erase(remove_if(all(a), f), a.end()); }
template<class T>inline T Age(T n, T m)noexcept { return (n + m - 1) / m; }
template<class T>inline T Age2(T n, T m)noexcept { return Age(n, m) * m; }
template<class T>inline T Tri(T n)noexcept { return (n & 1) ? (n + 1) / 2 * n : n / 2 * (n + 1); }
template<class T = long long>inline T BIT(int b)noexcept { return T{ 1 } << b; }
template<class T>inline T Gcd(T n, T m)noexcept { return m ? Gcd(m, n % m) : n; }
template<class T>inline T Lcm(T n, T m)noexcept { return n / Gcd(n, m) * m; }
template<class T>inline T Pow(T a, T n)noexcept { T r = 1; while (n > 0) { if (n & 1)r *= a; a *= a; n /= 2; }return r; }
template<class T>inline T Powmod(T a, T n, T m = MOD)noexcept { T r = 1; while (n > 0) { if (n & 1)r = r * a % m, n--; else a = a * a % m, n /= 2; }return r; }
template<class T>inline bool chmax(T& a, const T& b)noexcept { if (a < b) { a = b; return true; } return false; }
template<class T>inline bool chmin(T& a, const T& b)noexcept { if (a > b) { a = b; return true; } return false; }
template<class T>inline bool inRange(const T& v, const T& min, const T& max)noexcept { return min <= v && v <= max; }
inline string operator*(string s, int n)noexcept { string ret; rep(i, n)ret += s; return ret; }

// --- input --- //
#if defined(_WIN32) || defined(ONLINE_JUDGE)
#define getchar_unlocked _getchar_nolock
#define putchar_unlocked _putchar_nolock
#endif
inline int gc()noexcept { return getchar_unlocked(); }
template<class T>inline void InputF(T& v)noexcept { cin >> v; }
inline void InputF(char& v)noexcept { while (isspace(v = gc())); }
inline void InputF(string& v)noexcept {
	char c; for (InputF(c); !isspace(c); c = gc())v += c;
}
inline void InputF(int& v)noexcept {
	bool neg = false; v = 0; char c; InputF(c);
	if (c == '-') { neg = true; c = gc(); }
	for (; isdigit(c); c = gc())v = v * 10 + (c - '0');
	if (neg)v = -v;
}
inline void InputF(long long& v)noexcept {
	bool neg = false; v = 0; char c; InputF(c);
	if (c == '-') { neg = true; c = gc(); }
	for (; isdigit(c); c = gc())v = v * 10 + (LL)(c - '0');
	if (neg)v = -v;
}
inline void InputF(double& v)noexcept {
	double dp = 1; bool neg = false, adp = false; v = 0; char c; InputF(c);
	if (c == '-') { neg = true; c = gc(); }
	for (; isdigit(c) || c == '.'; c = gc()) {
		if (c == '.')adp = true;
		else if (adp)v += (c - '0') * (dp *= 0.1);
		else v = v * 10 + (c - '0');
	}
	if (neg)v = -v;
}
template<class T, class U>inline void InputF(pair<T, U>& v)noexcept {
	InputF(v.first); InputF(v.second);
}
template<class T>inline void InputF(vector<T>& v)noexcept {
	for (auto& e : v)InputF(e);
}
template<class T>inline T InputF() { T v; InputF(v); return v; }
struct InputV {
	int n, m;
	InputV(int N) :n(N), m(0) {}
	InputV(pair<int, int> N) :n(N.first), m(N.second) {}
	template<class T>operator vector<T>()noexcept {
		vector<T> v(n); InputF(v); return v;
	}
	template<class T>operator vector<vector<T>>()noexcept {
		vector<vector<T>> v(n, vector<T>(m)); InputF(v); return v;
	}
};
struct Input {
	template<class T>operator T()noexcept { return InputF<T>(); }
	int operator--(int) { int v; InputF(v); v--; return v; }
	InputV operator[](int n)noexcept { return InputV(n); }
	InputV operator[](pair<int, int> n)noexcept { return InputV(n); }
	void operator()() {}
	template<class H, class...T>void operator()(H&& h, T&& ...t) {
		InputF(h); operator()(forward<T>(t)...);
	}
	template<class T, size_t W>array<vector<T>, W> get(int H) {
		array<vector<T>, W> ret;
		rep(i, H)rep(j, W) { T x = *this; ret[j].push_back(x); }
		return ret;
	}
}in;
#define input(type) InputF<type>()

// --- output --- //
struct BoolStr {
	const char* t, * f; BoolStr(const char* _t, const char* _f) :t(_t), f(_f) {}
}Yes("Yes", "No"), yes("yes", "no"), YES("YES", "NO"), Int("1", "0");
struct DivStr {
	const char* d, * l; DivStr(const char* _d, const char* _l) :d(_d), l(_l) {}
}spc(" ", "\n"), no_spc("", "\n"), end_line("\n", "\n"), comma(",", "\n"), no_endl(" ", "");
class Output {
	BoolStr B{ Yes }; DivStr D{ spc }; bool isPrint = true;
	void p(double v) { printf("%.20f", v); } void p(long double v) { printf("%.20Lf", v); }
	void p(int v) { printf("%d", v); }	void p(LL v) { printf("%lld", v); }
	void p(char v) { putchar(v); }		void p(bool v) { printf("%s", v ? B.t : B.f); }
	template<class T>void p(const T& v) { cout << v; }
	template<class T, class U>void p(const pair<T, U>& v) { p(v.first); printf("%s", D.d); p(v.second); }
	template<class T>void p(const vector<T>& v) { rep(i, sz(v)) { if (i)printf("%s", D.d); p(v[i]); } }
	template<class T>void p(const vector<vector<T>>& v) { rep(i, sz(v)) { if (i)printf("%s", D.l); p(v[i]); } }
	void p(const BoolStr& v) { B = v; isPrint = false; } void p(const DivStr& v) { D = v; isPrint = false; }
public:
	void operator()() { printf("%s", D.l); }
	template<class H>void operator()(H&& h) {
		p(h); if (isPrint)printf("%s", D.l); isPrint = true;
	}
	template<class H, class...T>void operator()(H&& h, T&& ...t) {
		p(h); if (isPrint)printf("%s", D.d); isPrint = true; operator()(forward<T>(t)...);
	}
	template<class...T>void exit(T&& ...t) {
		operator()(forward<T>(t)...); std::exit(EXIT_SUCCESS);
	}
}out;

// --- dump --- //
#if __has_include("dump.hpp")
#include "dump.hpp"
#else
#define dump(...) (void(0))
#endif

template<class F>auto MakeVector(size_t size, F f) {
	vector<decay_t<result_of_t<F(size_t)>>> res(size);
	for (size_t i = 0; i < size; ++i)res[i] = f(i);
	return res;
}
template<class T>vector<T> Slice(const vector<T>& v, size_t i, size_t len) {
	return i < v.size() ? vector<T>(v.begin() + i, v.begin() + min(i + len, v.size())) : vector<T>();
}
template<class T, class F>void Each(T& v, F f) {
	for (auto& e : v)f(e);
}
template<class T, class F>auto Map(const vector<T>& v, F f) {
	vector<decay_t<result_of_t<F(T)>>> res(v.size());
	size_t i = 0; for (const auto& e : v)res[i++] = f(e);
	return res;
}
template<class T, class F>auto MapIndex(const vector<T>& v, F f) {
	vector<decay_t<result_of_t<F(size_t, T)>>> res(v.size());
	for (size_t i = 0; i < v.size(); ++i)res[i] = f(i, v[i]);
	return res;
}
template<class T, class F>vector<T> Select(const vector<T>& v, F f) {
	vector<T> res;
	for (const auto& e : v)if (f(e))res.push_back(e);
	return res;
}

// ---------------------------------------------------------------- //

constexpr bool Equal(ld a, ld b)noexcept { return a < b ? b - a < EPS : a - b < EPS; }

struct Vec2 {
	ld x, y;
	constexpr Vec2()noexcept :x(0), y(0) {}
	constexpr Vec2(ld _x, ld _y)noexcept :x(_x), y(_y) {}
	constexpr bool operator==(const Vec2& v)const noexcept { return Equal(x, v.x) && Equal(y, v.y); }
	constexpr bool operator!=(const Vec2& v)const noexcept { return !(*this == v); }
	constexpr bool operator<(const Vec2& v)const noexcept { return x < v.x - EPS && y < v.y - EPS; }
	constexpr bool operator<=(const Vec2& v)const noexcept { return x < v.x + EPS && y < v.y + EPS; }
	constexpr Vec2 operator+()const noexcept { return *this; }
	constexpr Vec2 operator-()const noexcept { return { -x,-y }; }
	constexpr Vec2 operator+(const Vec2& v)const noexcept { return Vec2(*this) += v; }
	constexpr Vec2 operator-(const Vec2& v)const noexcept { return Vec2(*this) -= v; }
	constexpr Vec2 operator*(const Vec2& v)const noexcept { return Vec2(*this) *= v; }
	constexpr Vec2 operator/(const Vec2& v)const noexcept { return Vec2(*this) /= v; }
	constexpr Vec2 operator+(ld n)const noexcept { return Vec2(*this) += Vec2(n, n); }
	constexpr Vec2 operator-(ld n)const noexcept { return Vec2(*this) -= Vec2(n, n); }
	constexpr Vec2 operator*(ld n)const noexcept { return Vec2(*this) *= Vec2(n, n); }
	constexpr Vec2 operator/(ld n)const noexcept { return Vec2(*this) /= Vec2(n, n); }
	constexpr Vec2& operator+=(const Vec2& v)noexcept { x += v.x; y += v.y; return *this; }
	constexpr Vec2& operator-=(const Vec2& v)noexcept { x -= v.x; y -= v.y; return *this; }
	constexpr Vec2& operator*=(const Vec2& v)noexcept { x *= v.x; y *= v.y; return *this; }
	constexpr Vec2& operator/=(const Vec2& v)noexcept { x /= v.x; y /= v.y; return *this; }
	constexpr Vec2& operator+=(ld n)noexcept { x += n; x += n; return *this; }
	constexpr Vec2& operator-=(ld n)noexcept { x -= n; x -= n; return *this; }
	constexpr Vec2& operator*=(ld n)noexcept { x *= n; x *= n; return *this; }
	constexpr Vec2& operator/=(ld n)noexcept { x /= n; x /= n; return *this; }
	constexpr ld operator[](size_t i)const noexcept { return i == 0 ? x : i == 1 ? y : 0; }
	ld manhattan(const Vec2& v)const noexcept { return std::abs(x - v.x) + std::abs(y - v.y); }
	ld dist(const Vec2& v)const noexcept { return hypot(x - v.x, y - v.y); }
	Vec2 abs(const Vec2& v)const noexcept { return { std::abs(x - v.x),std::abs(y - v.y) }; }
	Vec2& swap()noexcept { std::swap(x, y); return *this; }
	ld sqr_norm()const { return x * x + y * y; }
	ld norm()const { return sqrt(sqr_norm()); }
	Vec2 rotate90()const { return { y,-x }; }
	Vec2 rotate180()const { return { -x,-y }; }
	Vec2 rotate270()const { return { -y,x }; }
};
ostream& operator<<(ostream& os, const Vec2& v)noexcept { return os << '(' << v.x << ',' << v.y << ')'; }
istream& operator>>(istream& is, Vec2& v)noexcept { return is >> v.x >> v.y; }

ld TriangleArea(ld a, ld b, ld c) {
	ld s = (a + b + c) / 2;
	return sqrt(s * (s - a) * (s - b) * (s - c));
}
ld TriangleArea(const Vec2& v1, const Vec2& v2, const Vec2& v3) {
	return TriangleArea(v1.dist(v2), v1.dist(v3), v2.dist(v3));
}

struct Circle {
	Vec2 center; ld r;
	constexpr Circle()noexcept :center(), r(0) {}
	constexpr Circle(ld _r)noexcept : center(), r(_r) {}
	constexpr Circle(ld _x, ld _y, ld _r)noexcept : center(_x, _y), r(_r) {}
	constexpr Circle(const Vec2& _c, ld _r)noexcept : center(_c), r(_r) {}
	constexpr bool operator==(const Circle& c)const noexcept { return center == c.center && Equal(r, c.r); }
	constexpr bool operator!=(const Circle& c)const noexcept { return !(*this == c); }
	constexpr Circle& operator+(const Vec2& v)const noexcept { return Circle(*this) += v; }
	constexpr Circle& operator-(const Vec2& v)const noexcept { return Circle(*this) -= v; }
	constexpr Circle& operator+=(const Vec2& v)noexcept { center += v; return *this; }
	constexpr Circle& operator-=(const Vec2& v)noexcept { center -= v; return *this; }
	constexpr ld top_y()const noexcept { return center.y - r; }
	constexpr ld bottom_y()const noexcept { return center.y + r; }
	constexpr ld left_x()const noexcept { return center.x - r; }
	constexpr ld right_x()const noexcept { return center.x + r; }
	constexpr Vec2 top()const noexcept { return center - Vec2(0, r); }
	constexpr Vec2 bottom()const noexcept { return center + Vec2(0, r); }
	constexpr Vec2 left()const noexcept { return center - Vec2(r, 0); }
	constexpr Vec2 right()const noexcept { return center + Vec2(r, 0); }
	ld dist(const Vec2& p)const noexcept { return max<ld>(0, center.dist(p) - r); }
	ld dist(const Circle& c)const noexcept { return max<ld>(0, center.dist(c.center) - r - c.r); }
	constexpr ld area()const noexcept { return r * r * PI; }
	constexpr ld perimeter()const noexcept { return 2 * r * PI; }
	bool intersects(const Vec2& v) { return center.dist(v) < r + EPS; }
	bool intersects(const Circle& c) { return center.dist(c.center) < r + c.r + EPS; }
	bool contains(const Circle& c)const noexcept { return center.dist(c.center) + c.r < r - EPS; }
	bool tangent(const Circle& c)const noexcept {
		ld l1 = center.dist(c.center), l2 = r, l3 = c.r;
		return Equal(l1 + l2 + l3, max({ l1,l2,l3 }) * 2);
	}
	vector<Vec2> intersection(const Circle& c)noexcept {
		Vec2 v = center - c.center;
		ld l = v.norm();
		if (contains(c) || c.contains(*this)) {
			return {};
		} else if (Equal(l, r + c.r)) {
			return { c.center + v * (l / c.r) };
		} else if (Equal(r + l, c.r)) {
			return { c.center + v * (c.r / l) };
		} else if (Equal(c.r + l, r)) {
			return { center + v.rotate180() * (r / l) };
		} else if (intersects(c)) {
			ld area = TriangleArea(l, r, c.r);
			ld y = 2 * area / l, x = sqrt(r * r - y * y);
			Vec2 h = center + v.rotate180() * (x / l);
			Vec2 v2 = v.rotate90() * (y / l);
			return { h + v2,h - v2 };
		} else {
			return {};
		}
	}
};
ostream& operator<<(ostream& os, const Circle& c)noexcept {
	return os << '(' << c.center.x << ',' << c.center.y << ',' << c.r << ')';
}
istream& operator>>(istream& is, Circle& c)noexcept { return is >> c.center >> c.r; }

int main() {
	int n = in, k = in;
	vector<Vec2> xy(n); vector<ld> c(n);
	rep(i, n)in(xy[i], c[i]);

	auto check = [&](ld time)->bool {
		vector<Circle> circle = MapIndex(c, [&](size_t i, ld C) {return Circle(xy[i], time / c[i]); });
		vector<Vec2> can = xy;
		rep(i, n)FOR(j, i + 1, n) {
			auto tmp = circle[i].intersection(circle[j]);
			can.insert(can.end(), all(tmp));
		}
		for (auto v : can) {
			int cnt = 0;
			rep(i, n)cnt += circle[i].intersects(v);
			if (cnt >= k)return true;
		}
		return false;
	};

	ld ng = 0, ok = 600009;
	rep(_, 100) {
		ld mid = (ng + ok) / 2;
		(check(mid) ? ok : ng) = mid;
	}
	out(ok);
}

Measured memory_bytes: 512