#include <bits/stdc++.h>

using namespace std;
using LL = long long;

const double EPS = 1e-8;

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

    int n , m;
    cin >> n >> m;

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

    vector<double> b(n);
    auto check = [&](double mid){

        for(int i = 0 ; i < n ; i ++ )
            b[i] = (double)y[i] - (double) x[i] * mid;

        vector<double> f;
        for(int i = 0 ; i < n ; i ++ ){
            auto it = lower_bound(f.begin() , f.end() , b[i]);
            if(it == f.end()) f.push_back(b[i]);
            else *it = b[i];
        }
        return (int)f.size() >= m;
    };

    double l = -1e9 , r = 1e9;
    int cnt = 0;
    while(r - l > EPS && cnt <= 70){
        cnt ++;
        double mid = (l + r) / 2;
        if(check(mid)) l = mid;
        else r = mid;
    }

    cout << fixed << setprecision(9) << l;

    return 0;
}