Kurcina

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            double d = double.Parse(Console.ReadLine());
            double n = double.Parse(Console.ReadLine());
            double s = double.Parse(Console.ReadLine());
            double dc = d * 100;
            Console.WriteLine(Math.Round((dc - n * s) / (n + 1), 2));
        }
    }
}