Random

            Random ran = new Random();

            int[] ranges = new int[] { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
                10, 10, 10, 10,
                25, 25, 25,
                50, 50,
                75,
                100,
                75,
                50, 50,
                25, 25, 25,
                10, 10, 10, 10,
                5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5 };
            int MaxRange = ranges[ran.Next(ranges.Length)];
            double RandomReward = ran.Next(MaxRange) * .01;

            return RandomReward;