/*
@Date    : 2023-10-28 21:38:16
@Author  : Adscn ([email protected])
@Link    : http://www.cnblogs.com/LLCSBlog
*/
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
#define IL inline
#define RG register
#define gi geti<int>()
#define gl geti<ll>()
#define gc getchar()
#define File(a) freopen(a".in","r",stdin);freopen(a".out","w",stdout)
template<typename T>IL bool chkmax(T &x,const T &y){return x<y?x=y,1:0;}
template<typename T>IL bool chkmin(T &x,const T &y){return x>y?x=y,1:0;}
template<typename T>
IL T geti()
{
	RG T xi=0;
	RG char ch=gc;
	bool f=0;
	while(!isdigit(ch))ch=='-'?f=1:f,ch=gc;
	while(isdigit(ch))xi=xi*10+ch-48,ch=gc;
	return f?-xi:xi;
}
template<typename T>
IL void pi(T k,char ch=0)
{
	if(k<0)k=-k,putchar('-');
	if(k>=10)pi(k/10);
	putchar(k%10+'0');
	if(ch)putchar(ch);
}
/*
IL unsigned int LOG2(unsigned int x)
{
	unsigned int ret;
	__asm__ __volatile__ ("bsrl %1, %%eax":"=a"(ret):"m"(x));
	return ret;
}
*/
const int N=1e5+7;
const double eps=1e-7;
int n,k;
int px[N],py[N];
double t[N];
double dp[N];
bool check(double s)
{
	for(int i=1;i<=n;++i)t[i]=py[i]-s*px[i];
	dp[0]=-2e18;
	int len=0;
	for(int i=1;i<=n;++i){
		if(t[i]>=dp[len])dp[++len]=t[i];
		else{
			int pos=upper_bound(dp+1,dp+len+1,t[i])-dp;
			dp[pos+1]=t[i];
		}
	}
	return len>=k;
}
int main(void)
{
	#ifndef ONLINE_JUDGE
//	File("");
	#endif
	n=gi,k=gi;
	for(int i=1;i<=n;++i)px[i]=gi,py[i]=gi;
	double l=-1e9,r=1e9;
	while(l+eps<r)
	{
		double mid=(l+r)/2;
		if(check(mid))l=mid;
		else r=mid-eps;
	}
	printf("%.9f",l);
	return 0;
}