#include<cstdio>

#include<algorithm>

#include<cmath>

using namespace std;

#define EPS 0.000001

int n,x[60010],v[60010];

double calc(double p)

{

	double res=0;

	for(int i=1;i<=n;++i)

	  res=max(res,fabs(p-(double)x[i])/(double)v[i]);

	return res;

}

int main()

{

//	freopen("b.in","r",stdin);

	scanf("%d",&n);

	for(int i=1;i<=n;++i)

	  scanf("%d",&x[i]);

	for(int i=1;i<=n;++i)

	  scanf("%d",&v[i]);

	double l=1.0,r=1000000000.0;

	while(r-l>EPS)

	  {

	  	double m1=l+(r-l)/3.0;

	  	double m2=r-(r-l)/3.0;

	  	double t1=calc(m1),t2=calc(m2);

	  	if(t1>t2)

	  	  l=m1;

	  	else

	  	  r=m2;

	  }

	printf("%.12lf\n",calc(l));

	return 0;

}