import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        double totalWork = sc.nextDouble();
        double individualRate = sc.nextDouble();
        int numOfWorkers = sc.nextInt();
        double workerRate = sc.nextDouble();

        // Validate totalWork
        if (totalWork < 1000 || totalWork > 10000) {
            System.out.println("Invalid input");
            return;
        }

        // Compute days (–1 if that option can’t work)
        double individualDays = (individualRate == 0) 
            ? -1 
            : totalWork / individualRate;
        double groupDays = (numOfWorkers == 0 || workerRate == 0) 
            ? -1 
            : totalWork / (numOfWorkers * workerRate);

        // Print individual result
        if (individualDays < 0) {
            System.out.println(-1);
        } else {
            System.out.printf("%.1f%n", individualDays);
        }

        // Print group result
        if (groupDays < 0) {
            System.out.println(-1);
        } else {
            System.out.printf("%.1f%n", groupDays);
        }

        // Only when both options succeed within the 10-day limit
        if (individualDays >= 0 && groupDays >= 0
            && individualDays <= 10.0
            && groupDays <= 10.0) {
            System.out.println("Valid Input");
        }
    }
}