public class Basics {
    static double gst(double amount, double rate) { return Math.round(amount * rate * 100) / 100.0; }
    public static void main(String[] args) {
        String customer = "Sharma Traders";
        int qty = 12; double rate = 60.0;
        double amount = qty * rate;
        System.out.printf("%s: %d x %.2f = %.2f, GST %.2f%n", customer, qty, rate, amount, gst(amount, 0.18));
        int[] marks = {78, 91, 45, 33};
        int passed = 0;
        for (int m : marks) { if (m >= 40) passed++; }
        System.out.println("Passed: " + passed);
    }
}