#include #define ll long long #define INF 1000000005 #define MOD 1000000007 #define EPS 1e-10 #define rep(i,n) for(int i=0;i<(int)(n);++i) #define rrep(i,n) for(int i=(int)(n)-1;i>=0;--i) #define srep(i,s,t) for(int i=(int)(s);i<(int)(t);++i) #define each(a,b) for(auto& (a): (b)) #define all(v) (v).begin(),(v).end() #define len(v) (int)(v).size() #define zip(v) sort(all(v)),v.erase(unique(all(v)),v.end()) #define cmx(x,y) x=max(x,y) #define cmn(x,y) x=min(x,y) #define fi first #define se second #define pb push_back #define show(x) cout<<#x<<" = "<<(x)< P; typedef pair pll; typedef vector vi; typedef vector vvi; typedef vector vl; typedef vector vvl; typedef vector vd; typedef vector

vp; typedef vector vs; const int MAX_N = 100005; int main() { cin.tie(0); ios::sync_with_stdio(false); double P,Q; cin >> P >> Q; P /= 100.0, Q /= 100.0; printf("%.12lf\n",(double)P*Q*100.0/(P*Q+(1.0-P)*(1.0-Q))); return 0; }