1.
import java.util.Scanner;

/**
 * FWP, Ausgewählte Probleme aus dem ACM Programming Contest, SS10 
 * Problem: 10056 - What is the Probability ?
 * Link: http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=226&page=show_problem&problem=997
 * 
 * @author Siegfried Ippisch
 * @author Martin Lambeck
 * @version 1.0
 * 
 * Method : -
 * Status : Accepted
 * Runtime: 0.632
 */
public class WhatIsTheProbability {
	
	static Scanner in = new Scanner(System.in);
	
	public static void main (String...strings)
	{
		int cases = in.nextInt();
		
		for (int i = 0; i < cases; i++)
		{
			testcase();
		}
	
	}
	
	static void testcase()
	{
		int players = in.nextInt();
		double p = in.nextDouble();
		int winner = in.nextInt() -1;
		
		double rem = 1.0;

		double wp = 0.0;
		


		for (int pl = 0; pl < players; pl++)
		{
			double w = rem * p;
			
			if (pl == winner)
				wp = w;
			
			rem -= w;
		}
		
		wp = (1.0/(1.0-rem)) * wp;
		//wp = 
//		while (rem >= 0.00001)
//		{
//			wp += rem * firstwp;
//			rem = firstrem * rem;
//		}
		
		System.out.printf("%.4f\n", p == 0 ? 0.0 : wp);
	}
}