import java.util.Scanner;

public class StudentGradingSystem {

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

        // Read student type
        if (!scanner.hasNextLine()) {
            System.out.println("Invalid input");
            scanner.close();
            return;
        }
        String studentType = scanner.nextLine().trim();
        if (!(studentType.equals("Undergraduate") || studentType.equals("Postgraduate"))) {
            System.out.println("Invalid input");
            scanner.close();
            return;
        }

        // Read name
        if (!scanner.hasNextLine()) {
            System.out.println("Invalid input");
            scanner.close();
            return;
        }
        String name = scanner.nextLine().trim();

        // Read ID
        if (!scanner.hasNextLine()) {
            System.out.println("Invalid input");
            scanner.close();
            return;
        }
        String id = scanner.nextLine().trim();
        // Optionally, you can validate that ID is numeric, but your spec doesn't say it's required

        // Read number of grades
        if (!scanner.hasNextLine()) {
            System.out.println("Invalid input");
            scanner.close();
            return;
        }
        String numGradesStr = scanner.nextLine().trim();
        int numGrades;
        try {
            numGrades = Integer.parseInt(numGradesStr);
        } catch (NumberFormatException e) {
            System.out.println("Invalid input");
            scanner.close();
            return;
        }

        if (numGrades < 0) {
            System.out.println("Invalid input");
            scanner.close();
            return;
        }

        double sum = 0.0;
        for (int i = 0; i < numGrades; i++) {
            if (!scanner.hasNextLine()) {
                System.out.println("Invalid input");
                scanner.close();
                return;
            }
            String gradeStr = scanner.nextLine().trim();
            int grade;
            try {
                grade = Integer.parseInt(gradeStr);
            } catch (NumberFormatException e) {
                System.out.println("Invalid input");
                scanner.close();
                return;
            }
            // Validate grade
            if (grade < 0 || grade > 100) {
                System.out.println("Invalid input");
                scanner.close();
                return;
            }
            sum += grade;
        }

        if (numGrades == 0) {
            // If there are zero grades, average is 0.00 maybe?
            // You can define behaviour — here I'll print 0.00
            System.out.printf("%.2f%n", 0.0);
        } else {
            double average = sum / numGrades;
            System.out.printf("%.2f%n", average);
        }

        scanner.close();
    }
}