private static int DoComputation(int start){ int sum = 0; for (var value = 1; value <= start; value++){ sum += value; } return sum; } public static void Main(){ int sum = 0; Task<int>[] taskArray = { Task<int>.Factory.StartNew(() => DoComputation(3)), Task<int>.Factory.StartNew(() => DoComputation(4)) }; for (int i = 0; i < taskArray.Length; i++){ sum += taskArray[i].Result; } Console.WriteLine("sum"); Console.ReadLine(); }