#include <bits/stdc++.h>

using namespace std;

#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()

typedef long long ll;
typedef pair<int, int> pii;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

template<typename T>
std::ostream& operator << (std::ostream& os, const vector<T>& a) {
    for (const T& x : a) {
        os << x << ' ';
    }
    return os;
}

const double INF = 1e18;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, k;
    cin >> n >> k;
    vector<int> x(n), y(n);
    for (int i = 0; i < n; ++i) {
        cin >> x[i] >> y[i];
    }

    double low = -1e10, high = 1e10;
    for (int it = 0; it < 60; ++it) {
        double mid = (low + high) / 2;
        vector<double> a(n);
        for (int i = 0; i < n; ++i) {
            a[i] = y[i] - mid * x[i];
        }
        vector<double> dp(n + 1, INF);
        dp[0] = -INF;
        for (int i = 0; i < n; ++i) {
            int j = upper_bound(all(dp), a[i]) - dp.begin();
            dp[j] = a[i];
        }
        int ans = n;
        while (dp[ans] > INF / 2) {
            --ans;
        }
        if (ans >= k) {
            low = mid;
        } else {
            high = mid;
        }
    }

    cout.precision(15);
    cout << (low + high) / 2 << '\n';

    return 0;
}