#include<bits/stdc++.h>
using namespace std;
int main(){
    double t1,t2,t3,x1,x2,x3;
    while(cin>>t1>>t2>>t3>>x1>>x3)
    printf("%f\n",(t2*(x1-x3)+t1*x3-t3*x1)/(t1-t3));
}