using System;

public class Program

{

    public static void Main()

    {

        double days = double.Parse(Console.ReadLine());

        double cooks = double.Parse(Console.ReadLine());

        double cakes = double.Parse(Console.ReadLine());

        double waffles = double.Parse(Console.ReadLine());

        double pancakes = double.Parse(Console.ReadLine());

        double pcakes = cakes * 45; 

        double pwaffles = waffles * 5.80;

        double ppancakes = pancakes * 3.20;

        double overallpriceforaday = (pcakes + pwaffles + ppancakes) * cooks;

        double overallprice = overallpriceforaday * days;

        double final = overallprice / 8;

        double allfinal = overallprice - final;

        Console.WriteLine(Math.Round(allfinal, 2));

    }

}