#include <iostream>
#include<algorithm>
#include<cstdio>
using namespace std;
struct mooncake{
   float mount;
   float price;
   float unit;
};
int cmp(mooncake a,mooncake b){
       return a.unit>b.unit;
 }
int main()
{
    int n;
   scanf("%d",&n);
    int need;
    scanf("%d",&need);
    mooncake *a=new mooncake [n];
    for(int i=0;i<n;i++){
        scanf("%f",&a[i].mount);
    }
    for(int i=0;i<n;i++){
        scanf("%f",&a[i].price);
    }
    for(int i=0;i<n;i++){
        a[i].unit=a[i].price/a[i].mount;
    }
    sort(a,a+n,cmp);
    float result =0.0;
    for(int i=0;i<n;i++){
        if(a[i].mount<=need){
            result=result+a[i].price;
        }else{
            result=result+a[i].unit*need;
            break;
        }
        need=need-a[i].mount;
    }
    printf("%.2f",result);
    return 0;
}