#include<bits/stdc++.h> using namespace std; int main(){ int x,y,t,ans=0,a; double m=0.0,b=0.0,c=0.0; cin>>x>>y>>t; a=x*t; m=(double)a/(y-x); c=x; b=m*c; ans=a+b; cout<<ans; return 0; }