namespace RegexEx
{
    using System;

    public class RegexEx
    {
        public static void Main(string[] args)
        {
            decimal skumriaPricePerKilo = decimal.Parse(Console.ReadLine());
            decimal cacaPricePerKilo = decimal.Parse(Console.ReadLine());
            decimal kgPalamud = decimal.Parse(Console.ReadLine());
            decimal kgSafrid = decimal.Parse(Console.ReadLine());
            decimal kgMidi = decimal.Parse(Console.ReadLine());

            decimal totalMidiPrice = kgMidi * 7.50m;

            decimal palamudPrice = skumriaPricePerKilo + skumriaPricePerKilo * 0.6m;
            decimal totalPalamudPrice = palamudPrice * kgPalamud;

            decimal safridPrice = cacaPricePerKilo + cacaPricePerKilo * 0.8m;
            decimal totalSafridPrice = safridPrice * kgSafrid;

            decimal totalPrice = totalMidiPrice + totalPalamudPrice + totalSafridPrice;
            Console.WriteLine($"{totalPrice:F2}");
        }
    }
}