#include<iostream>
#include<algorithm>
using namespace std;
const int N = 1100;

struct Cake{
    double s; // 总量
    double w, avg;
}cake[N];
bool cmp(Cake a,Cake b)
{
    return a.avg > b.avg; 
}
int main()
{
    int n; // 需求req
    double req;// 注意需求量一定要为double
    cin >> n >> req;
    for(int i = 0;i < n;i++)    cin >> cake[i].s;
    for(int i = 0;i < n;i++){
        cin >> cake[i].w;
        cake[i].avg = cake[i].w / cake[i].s; // 单价
    }
    sort(cake,cake+n,cmp);
    double sum = 0.0;
    for(int i = 0;i < n;i++)
    {
        if(req >= cake[i].s) sum += cake[i].w, req -= cake[i].s;
        else{
            sum += cake[i].avg * req;
            break;
        }
    }
    printf("%.2lf",sum);
    return 0;
}