using System;

public class Program

{

    public static void Main()

    {

        int numberDays = int.Parse(Console.ReadLine());

        int numberConfectioners = int.Parse(Console.ReadLine());

        int numberCakes = int.Parse(Console.ReadLine());

        int numberWaffles = int.Parse(Console.ReadLine());

        int numberPancakes = int.Parse(Console.ReadLine());

        double finalPriceDaily = numberCakes * 45 + numberWaffles * 5.80 + numberPancakes * 3.20;

double finalPrice = finalPriceDaily * numberConfectioners * numberDays;

        finalPrice = finalPrice - (finalPrice / 8);

        Console.WriteLine("{0:F2}", finalPrice);

    }

}