#include<bits/stdc++.h>
using namespace std;
using ll = long long;
template<class T> using vt = vector<T>;
template<class T> using vvt = vector<vt<T>>;
template<class T> using ttt = tuple<T,T>;
using tii = tuple<int,int>;
using tiii = tuple<int,int,int>;
using vi = vector<int>;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define pb push_back
#define ALL(a) (a).begin(),(a).end()
#define FST first
#define SEC second
#define DEB cerr<<"!"<<endl
#define SHOW(a,b) cerr<<(a)<<" "<<(b)<<endl
#define DIV int(1e9+7)
const int INF = (INT_MAX/2);
const ll LLINF = (LLONG_MAX/2);
const double eps = 1e-8;
//const double PI = M_PI;  
inline ll pow(ll x,ll n,ll m){ll r=1;while(n>0){if((n&1)==1)r=r*x%m;x=x*x%m;n>>=1;}return r%m;}
inline ll lcm(ll d1, ll d2){return d1 / __gcd(d1, d2) * d2;}

/* Coding space */
std::random_device seed_gen;
std::default_random_engine engine(seed_gen());
std::uniform_real_distribution<> dist(0.0, 1.0);
int main(){
  int n; cin >> n;
  double p,q; cin >> p >> q;
  double ans = 0.0;
  
  
  rep(i,1000000){
    int now = 1;
    rep(j,100){
      double t = dist(engine);
      if(t < p)  now--;
      else if(t < p + q)  now++;
      else  break;
      if(now == 0){ans += 1.0; break;}
    }
  }
  cout <<fixed << setprecision(10) <<  ans / 1000000.0 << endl;
}