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

namespace IGCalculator
{
    class Program
    {
        static public double I(double p, double n)
        {
            double result = (-p * Math.Log(p, 2) - n * Math.Log(n, 2));
            if (result.ToString() == "NaN")
            {
                return 0;
            }
            return result;
        }

        static public double IG(double x1, double p1, double q1, double x2, double p2, double q2, double x3, double p3, double q3)
        {
            return x1 * I(p1, q1) + x2 * I(p2, q2) + x3 * I(p3, q3);
        }

        static void Main(string[] args)
        {
            double x1;
            double p1;
            double q1;
            x1 = Double.Parse(Console.ReadLine()) / Double.Parse(Console.ReadLine());
            p1 = Double.Parse(Console.ReadLine()) / Double.Parse(Console.ReadLine());
            q1 = Double.Parse(Console.ReadLine()) / Double.Parse(Console.ReadLine());

            double x2;
            double p2;
            double q2;
            x2 = Double.Parse(Console.ReadLine()) / Double.Parse(Console.ReadLine());
            p2 = Double.Parse(Console.ReadLine()) / Double.Parse(Console.ReadLine());
            q2 = Double.Parse(Console.ReadLine()) / Double.Parse(Console.ReadLine());

            double x3;
            double p3;
            double q3;
            x3 = Double.Parse(Console.ReadLine()) / Double.Parse(Console.ReadLine());
            p3 = Double.Parse(Console.ReadLine()) / Double.Parse(Console.ReadLine());
            q3 = Double.Parse(Console.ReadLine()) / Double.Parse(Console.ReadLine());

            Console.WriteLine("IG = {0}", IG(x1, p1, q1, x2, p2, q2, x3, p3, q3));
            Console.ReadLine();
        }
    }
}