#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<long double> dist(0.0, 1.0);
int main(){
  int n; cin >> n;
  long double p,q; cin >> p >> q;
  long double ans = 0.0;
  long double d[1001] = {};
  d[1] = p;
  const ll X = 1000000;
  const ll iX = 1000;
  rep(i,1001) if(i!=0)d[i] *= d[i-1]*p;
  rep(i,X){
    int now = 1;
    rep(j,1000){
      long double t = dist(engine);
      //cerr << t << endl;
      if(t < p)  now--;
      else if(t < p + q)  now++;
      else  break;
      if(now == 0){ans += 1.0; break;}
      if(now >= n){break;}
      if( j == iX -1) {ans += d[now]; break;}
    }
  }
  cout <<fixed << setprecision(10) <<  ans / (1.0*X) << endl;
}