using System;

namespace fruitShop
{
    class Program
    {
        static void Main(string[] args)
        {
            string product = Console.ReadLine();
            string dayOfTheWeek = Console.ReadLine();
            double quantity = double.Parse(Console.ReadLine());



            if (dayOfTheWeek == "Monday" || dayOfTheWeek == "Tuesday" || dayOfTheWeek == "Wednesday" || dayOfTheWeek == "Thursday" || dayOfTheWeek == "Friday")
            {

                if (product == "banana")
                {

                    Console.WriteLine($"{quantity * 2.50:f2}");

                }

                if (product == "apple")
                {

                    Console.WriteLine($"{quantity * 1.20:f2}");

                }

                if (product == "orange")
                {

                    Console.WriteLine($"{quantity * 0.85:f2}");

                }

                if (product == "grapefruit")
                {

                    Console.WriteLine($"{quantity * 1.45:f2}");

                }

                if (product == "kiwi")
                {

                    Console.WriteLine($"{quantity * 2.70:f2}");

                }
                if (product == "pineaple")
                {

                    Console.WriteLine($"{quantity * 5.50:f2}");

                }
                if (product == "grapes")
                {

                    Console.WriteLine($"{quantity * 3.85:f2}");

                }



            }

            else if (dayOfTheWeek == "Saturday" || dayOfTheWeek == "Sunday")
            {
                if (product == "banana")
                {

                    Console.WriteLine($"{quantity * 2.70:f2}");

                }

                if (product == "apple")
                {

                    Console.WriteLine($"{quantity * 1.25:f2}");

                }

                if (product == "orange")
                {

                    Console.WriteLine($"{quantity * 0.90:f2}");

                }

                if (product == "grapefruit")
                {

                    Console.WriteLine($"{quantity * 1.60:f2}");

                }

                if (product == "kiwi")
                {

                    Console.WriteLine($"{quantity * 3.00:f2}");

                }
                if (product == "pineaple")
                {

                    Console.WriteLine($"{quantity * 5.60:f2}");

                }
                if (product == "grapes")
                {

                    Console.WriteLine($"{quantity * 4.20:f2}");

                }


            }
            else
            {
                Console.WriteLine("error");
            }




        }

    }
}