#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using i64 = long long;

void solve() {
    int n, k;
    cin >> n >> k;
    vector<array<int, 2>> a(n);
    for (int i = 0; i < n; ++i) {
        int x, y;
        cin >> x >> y;
        a[i] = {x, y};
    }

    auto check = [&](double mid) -> bool {
        vector<double> p(n);
        for (int i = 0; i < n; ++i) {
            auto [x, y] = a[i];
            p[i] = y - mid * x;
        }
        vector<double> x;
        for (int i = 0; i < n; ++i) {
            auto pos = upper_bound(x.begin(), x.end(), p[i],
                                   [](double a, double b) { return a - b < -1e-12; });
            if (pos == x.end()) {
                x.push_back(p[i]);
            } else {
                *pos = p[i];
            }
            if (x.size() >= k) return 1;
        }
        return 0;
    };

    double l = -2e9 - 1, r = 2e9 + 1;
    while (l + 1e-12 < r) {
        double mid = (l + r) / 2;
        if (check(mid)) {
            l = mid;
        } else {
            r = mid;
        }
    }
    cout << fixed << setprecision(12);
    cout << l << '\n';
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }
    return 0;
}