I Understand there are many answers saying how to calculate percentile using LINQ, but I could not find any relevant answer for my problem.

I have a list of object, which contains time duration as one of the properties on which I have to calculate the percentile by grouping the list by name. Is there any easiest way to do this using linq in C#. 
My object looks like below:

```
class Performance{
        public string Name { get; set; }
        public Nullable<decimal> DurationMilliSeconds { get; set; }
        public string typeName { get; set; }
}

```