#include<bits/stdc++.h> using namespace std; int n; int main() { cin>>n; for(int i=1;i<=n;i++) { double ans=0; int a,b,c,d; char ch; cin>>a>>ch>>b>>ch>>c>>ch>>d; if(double((d-b)/(a-c))==0) ans=0.0001; else ans=double((d-b)/(a-c)); cout<<ans<<endl; } return 0; }