static void Main(string[] args)
{
var book = new Book("Scott's Grade Book");
book.AddGrade(89.1);
book.AddGrade(90.5);
book.AddGrade(77.5);
book.ComputeStatistics();
var stats = book.GetStatistics();
Console.WriteLine($"The average grade is {stats.Average}");
Console.WriteLine($"The highest grade is {stats.High}");
Console.WriteLine($"The lowest grade is {stats.Low}");
}
