int n, rand, count = 0, count1 = 0, count2 = 0;
            double avg;
            Console.WriteLine("enter a full number n");
            n = int.Parse(Console.ReadLine());
            Random randNum = new Random();
            for (int i = 1; i <= n; i++)
            {
                rand = randNum.Next(8, 11);

                if (rand == 8)
                count++;

                if (rand == 9)
                 count1++;

                if (rand == 10)
                count2++;

            }
            if((count > count1) && (count > count2))
             Console.WriteLine("8");

            if((count1 > count) && (count1 > count2))
             Console.WriteLine("9");

            if((count2 > count1)&&(count2 >count))
            Console.WriteLine("10");

            avg = (count * 8 + count1 * 9 + count2 * 10) / n;
            Console.WriteLine(avg);