using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("How much does your item cost?");

            double price = Convert.ToDouble(Console.ReadLine());

            double vatprice = vatmul(price);

            Console.WriteLine("£{0}",vatprice);

    }

    static double vatmul(double number)

    {

    double vat = number;

            double total = vat * 1.20;

            return total;

    }

}

​