#include<stdio.h>

void run(void){
  double p,q;
  scanf("%lf%lf",&p,&q);
  p/=100;
  q/=100;
  double ans=q*p/(q*p+(1-q)*(1-p));
  printf("%.7f\n",ans*100);
}

int main(void){
  run();
  return 0;
}