using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

​

            public class Data

            {

                public string Name { get; set; }

                public int AssessNumber { get; set; }

                public decimal Score { get; set; }

​

                public override string ToString()

                {

                    return Name + "\t" + AssessNumber + "\t" + Score;

                }

            }

​

public static class Program

{

    public static void Main()

    {

                var data = new List<Data>

    {

        {new Data { Name= "John", AssessNumber = 1,Score=90 }},

        {new Data { Name= "John", AssessNumber = 2,Score=88 }},

        {new Data { Name= "John", AssessNumber = 3,Score=67 }},

        {new Data { Name= "Steve", AssessNumber = 1,Score=98 }},

        {new Data { Name= "Steve", AssessNumber = 2,Score=90 }},

    };

                var results = data.GroupBy(x => x.Name).Select(x => new Data

                {

                    Name = x.Key,

                    AssessNumber = x.Max(z => z.AssessNumber),

                    Score = x.Average(z => z.Score)

                });

​

        results.Dump();

    }

    public static void Dump(this IEnumerable<Data> query)

    {

        foreach(var r in query)

        {

            Console.WriteLine(r);

        }

    }

}