无法将类型“double”隐式转换为“long”。存在显式转换（是否缺少强制转换？

问：

这是我的代码的第一部分，它声明并为其提供以下值：technology1.0

 static void Game1()
        {
            Random random = new Random();
            Int64 startingCash = random.Next(4000, 5000);
            Int64 startingVillagers = random.Next(4, 13);
            double technology = 1.0;
            Console.WriteLine("Your starting villagers are " + startingVillagers + ", and your starting cash is " + startingCash + ".");
            Console.ReadLine();
            MainGame(startingCash, startingVillagers, technology);
        }

这是我代码的第二部分，发生错误的地方，这里是导致错误的地方。:tecnology += 0.5

 else if (probability >= 7 && probability <= 10)
                {
                    technology += 0.5;
                    Console.WriteLine("Your tech has increased, you now have " + technology + " Tech points.");
                    Console.ReadLine();

我试过使用 ，但还没有找到解决方案。longDoubledouble