Program:

The source code to find the negative double numbers using Linq is given below. The given program is compiled and executed successfully on Microsoft Visual Studio.

//C# Program to find negative double numbers from 
//the list of objects using Linq.

using System;
using System.Linq;
using System.Collections.Generic;

class Demo
{
    static void Main(string[] args)
    {
        List<object> objectList = new List<object>()
        {
            101, "Amit", 102,"Joseph", -10.3, "RK Verma", 104, "Sanjay Shukla", 10.5F, "Pramod Pandey",-10.7
        };


        List<double> result = objectList.OfType<double>().Where(n=>n<0).ToList();

        foreach (double neg in result)
        {
            Console.WriteLine(neg + " ");
        } 
    }
}

Output:

-10.3
-10.7
Press any key to continue . . .

Explanation:

In the above program, we created a list of objects that contains different types of values then we find negative double numbers using OfType() and Where() method using the below code.

List<double> result = objectList.OfType<double>().Where(n=>n<0).ToList();