typedef long long ll;
typedef long double ld;

#include <bits/stdc++.h>
using namespace std;
#define int long long

signed main(){
    ll n,m;
    std::cin >> n>>m;
    vector<ld> a(n),b(n),p(n);
    for (int i = 0; i < n; i++) {
        std::cin >> a[i]>>b[i]>>p[i];
    }
    map<pair<ll,ll>,ld> memo;
    function<ld(ll,ll)> dfs = [&](ll i, ll j){
        if(memo.find({i,j})!=memo.end())return memo[{i,j}];
        if(i==n)return (ld)0;
        ld ma = 0;
        for (int k = 0; k < n; k++) {
            if(i&(1<<k))continue;
            if(j!=0)ma = max(ma, max(
                dfs(i+(1<<k), j)+1/a[k],
                (1/p[k])*(dfs(i+(1<<k), j)+1/b[k])+(1-1/p[k])*dfs(i,j-1)
            ));
            if(j==0){
                ma = max(ma, dfs(i+(1<<k), j)+1/a[k]);
            }
        }
        return memo[{i,j}]=ma;
    };
    std::cout << setprecision(20)<<dfs(0, m) << std::endl;
}