Linq c# simplify two list by keeping index and removing items that matches a null

I need to simplify two lists using linq keeping their index and removing pairs that might have a null/empty partner. Or if I could combine them into a dictionary of key-value pairs (int and decimal) that will also be great.

list1=["1","2","4","5","6"]
list2=["20.20","","",50.0,""]

to

list1=["1","5"]
list2=["20.20","50.0"]

I get the lists from a form collection of paymentcategory and amounts. The categories and amounts are dynamically generated.

>Solution :

I have solution using loop.

    var data = new Dictionary<int, decimal>()
    if(lis1.Count==list2.Count)
    {
       for (var i = 0; i < list1.Length; i++)
       {
          if (!string.IsNullOrEmpty(list1[i])&&!string.IsNullOrEmpty(list2[i]))
            data.Add(Convert.ToInt32(list1[i]),Convert.ToDecimal(list2[i]));
       }
   }

now your data variable have Dictionary with int and decimal data.

Note: The both list needs to have same number of data otherwise it will through IndexOutOfRange exception