using System;

public class Program

{

    public static void Main()

    {

        var prskumria = double.Parse(Console.ReadLine());

        var prcaca = double.Parse(Console.ReadLine());

        var kgpalamud = double.Parse(Console.ReadLine());

        var kgsafrid = double.Parse(Console.ReadLine());

        var kgmidi = double.Parse(Console.ReadLine());

        var prpalamid = prskumria*1.6;

        var sumpalamid = kgpalamud*prpalamid;

        var prsafrid = 1.8*prcaca;

        var sumsafrid = kgsafrid*prsafrid;

        var summidi = kgmidi*7.5;

        var total = sumpalamid+sumsafrid+summidi;

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

    }

}