import java.util.Scanner;

public class FruitShop {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        // banana / apple / orange / grapefruit / kiwi / pineapple / grapes

        String fruit = (scanner.nextLine());
        String dayOfWeek = (scanner.nextLine());
        double quantity = Double.parseDouble(scanner.nextLine());
        double totalPrice = 0;
        switch (dayOfWeek) {
            case "Monday":
            case "Tuesday":
            case "Wednesday":
            case "Thursday":
            case "Friday":
                switch (fruit) {
                    case "banana":
                        totalPrice = quantity * 2.50;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "apple":
                        totalPrice = quantity * 1.20;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "orange":
                        totalPrice = quantity * 0.85;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "grapefruit":
                        totalPrice = quantity * 1.45;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "kiwi":
                        totalPrice = quantity * 2.70;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "pineapple":
                        totalPrice = quantity * 5.50;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "grapes":
                        totalPrice = quantity * 3.85;
System.out.printf("%.2f", totalPrice);
                        break;
default: System.out.printf("error");
break;
                }

                break;
            case "Saturday":
            case "Sunday":
                switch (fruit) {
                    case "banana":
                        totalPrice = quantity * 2.70;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "apple":
                        totalPrice = quantity * 1.25;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "orange":
                        totalPrice = quantity * 0.90;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "grapefruit":
                        totalPrice = quantity * 1.60;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "kiwi":
                        totalPrice = quantity * 3.00;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "pineapple":
                        totalPrice = quantity * 5.60;
System.out.printf("%.2f", totalPrice);
                        break;
                    case "grapes":
                        totalPrice = quantity * 4.20;
System.out.printf("%.2f", totalPrice);
                        break;
default: System.out.printf("error");
break;
                }

                break;

            default:
                System.out.println("error");
                break;
        }

    }

}