gistfile1.java

import java.util.Scanner;


public class E {
	
	/**
	 * @param args
	 */
	private static int opp;
	private static int win;
	private static int lose;
	
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner in = new Scanner(System.in);
		
		int cases = in.nextInt();
		
		in.nextLine();
		
		for(int i=0;i<cases;i++){
			in.nextLine(); // ignore name
			
			opp = in.nextInt();
			
			win = in.nextInt();
			lose = in.nextInt();
			
			in.nextLine();
						
			System.out.printf("%.5f\n", doWork(1.0, 20, 0, 0));
		}
	}
	
	static double doWork(double propSoFar, int can, int can_wins, int opp_wins){
		if(can_wins >= 4)
			return propSoFar;
		
		if(opp_wins >= 4)
			return 0.0;
		
		if(can <= 0)
			return 0.0;
		
		double winProp = (1.0*can) / (can + opp);
		double loseProp = (1.0*opp) / (can + opp);
		
		return doWork(propSoFar * winProp, 20 + win, can_wins + 1, opp_wins)
			 + doWork(propSoFar * loseProp, 20 - lose, can_wins, opp_wins + 1);
	}
}