// editor3
// editor3
import java.util.Scanner;

public class ProjectCompletion {

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

        double totalWork = sc.nextDouble();
        double individualWorkRate = sc.nextDouble();
        int numberOfWorkers = sc.nextInt();
        double workRatePerWorker = scanner.nextDouble();
        if (totalWork <= 0) {
            System.out.println("Invalid input");
            return;
        }
        if (individualWorkRate <= 0) {
            System.out.println(-1);
        } else {
            double individualDays = totalWork / individualWorkRate;
            System.out.println(individualDays);
        }
        if (numberOfWorkers <= 0 || workRatePerWorker <= 0) {
            System.out.println(-1);
        } else {
            double groupWorkRate = numberOfWorkers * workRatePerWorker;
            double groupDays = totalWork / groupWorkRate;
            System.out.println(groupDays);
        }
    }
}