#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=(n)-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define pqueue(x) priority_queue<x,vector<x>,greater<x>>
#define all(x) (x).begin(),(x).end()
#define CST(x) cout<<fixed<<setprecision(x)
#define rev(x) reverse(x);
using ll=long long;
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
using pl=pair<ll,ll>;
using vpl=vector<pl>;
using vvpl=vector<vpl>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=2e9+1;
const ll INF=4e18;
const ll dy[8]={-1,0,1,0,1,1,-1,-1};
const ll dx[8]={0,-1,0,1,1,-1,1,-1};
template <typename T> inline bool chmax(T &a, T b) {
  return ((a < b) ? (a = b, true) : (false));
}
template <typename T> inline bool chmin(T &a, T b) {
  return ((a > b) ? (a = b, true) : (false));
}
using ld=long double;
vector<ld> p(3);
vector<map<ll,ld>> memo(15);
ld dp(ll v,ll len){
  if(v==0)return 0;
  if(len==0)return v;
  if(memo[v].count(len))return memo[v][len];
  ld ret=0;
  rep(bit,1<<v){
    ld prob=1;
    rep(i,v){
      if(bit>>i&1){
        if(i==0&&i==v-1)prob*=p[0];
        else if(i==0||i==v-1)prob*=p[1];
        else prob*=p[2];
      }
      else{
        if(i==0&&i==v-1)prob*=(ld)1.0-p[0];
        else if(i==0||i==v-1)prob*=(ld)1.0-p[1];
        else prob*=(ld)1.0-p[2];
      }
    }
    ll idx=0;
    ld rt=0;
    rep(i,v){
      if(bit>>i&1){
        rt+=dp(idx,len-1);
        idx=0;
      }
      else idx++;
    }
    rt+=dp(idx,len-1);
    ret+=prob*rt;
  }
  memo[v][len]=ret;
  return ret;
}
int main(){
  ll n;cin >> n;n=80-n;
  rep(i,3)cin >> p[i];rep(i,3)p[i]/=100;
  CST(10);
  cout << dp(14,n)*2 << endl;
}