More complicated Linq test, Average failed on iOS

LinqTest.cs

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

public class LinqTest : MonoBehaviour
{
    public class MyClass
    {
        public Vector3 MyVector;
    }

    public class Foo<T> where T : new()
    {
        public T Bar;

        // Random collection used to test SelectMany
        public List<T> Collection = new List<T>
        {
            new T(),
            new T(),
            new T(),
            new T(),
        };
    }

    private Dictionary<string, Foo<MyClass>> _testTarget;

    void Start()
    {
        _testTarget = new Dictionary<string, Foo<MyClass>>()
        {
            { "AAA", new Foo<MyClass> { Bar = new MyClass{ MyVector = new Vector3(Random.Range(-100, 100), Random.Range(-100, 100), Random.Range(-100, 100)) } } },
            { "BBB", new Foo<MyClass> { Bar = new MyClass{ MyVector = new Vector3(Random.Range(-100, 100), Random.Range(-100, 100), Random.Range(-100, 100)) } } },
            { "CCC", new Foo<MyClass> { Bar = new MyClass{ MyVector = new Vector3(Random.Range(-100, 100), Random.Range(-100, 100), Random.Range(-100, 100)) } } },
            { "DDD", new Foo<MyClass> { Bar = new MyClass{ MyVector = new Vector3(Random.Range(-100, 100), Random.Range(-100, 100), Random.Range(-100, 100)) } } },
            { "EEE", new Foo<MyClass> { Bar = new MyClass{ MyVector = new Vector3(Random.Range(-100, 100), Random.Range(-100, 100), Random.Range(-100, 100)) } } },
            { "FFF", new Foo<MyClass> { Bar = new MyClass{ MyVector = new Vector3(Random.Range(-100, 100), Random.Range(-100, 100), Random.Range(-100, 100)) } } },
            { "GGG", new Foo<MyClass> { Bar = new MyClass{ MyVector = new Vector3(Random.Range(-100, 100), Random.Range(-100, 100), Random.Range(-100, 100)) } } },
        };
    }

    void OnGUI()
    {
        if (GUILayout.Button("Sum projection"))
        {
            Debug.Log(_testTarget.Sum(x => x.Value.Bar.MyVector.x));
        }

        if (GUILayout.Button("Select"))
        {
            Debug.Log(_testTarget.Select(x => x.Value.Bar.MyVector.z).ElementAt(0));
        }

        if (GUILayout.Button("Select anonymous type"))
        {
            Debug.Log(_testTarget.Select(x => new {Name = "Bob", Age = x.Value.Bar.MyVector.y }).ElementAt(0).Name);
        }

        if (GUILayout.Button("Where"))
        {
            Debug.Log(_testTarget.Where(x => x.Value.Bar.MyVector.x < 0).ElementAt(0).Value.Bar.MyVector.y);
        }

        if (GUILayout.Button("Select many"))
        {
            Debug.Log(_testTarget.SelectMany(x => x.Value.Collection).ElementAt(0).MyVector.x);
        }

        if (GUILayout.Button("Any"))
        {
            Debug.Log(_testTarget.Any(x => x.Value.Bar.MyVector.y > 50));
        }

        if (GUILayout.Button("Min"))
        {
            Debug.Log(_testTarget.Min(x => x.Value.Bar.MyVector.z));
        }

        if (GUILayout.Button("Max"))
        {
            Debug.Log(_testTarget.Max(x => x.Value.Bar.MyVector.z));
        }

        if (GUILayout.Button("Average")) // Bad
        {
            Debug.Log(_testTarget.Average(x => x.Value.Bar.MyVector.z));
        }

        if (GUILayout.Button("Count"))
        {
            Debug.Log(_testTarget.Count(x => x.Value.Bar.MyVector.x < 0));
        }

        if (GUILayout.Button("Aggregate"))
        {
            Debug.Log(_testTarget.Aggregate((x, y) => new KeyValuePair<string, Foo<MyClass>>(x.Key, y.Value)).Value.Bar.MyVector.y);
        }

        if (GUILayout.Button("All"))
        {
            Debug.Log(_testTarget.All(x => x.Value.Bar.MyVector.y < 90));
        }

        if (GUILayout.Button("First or default"))
        {
            Debug.Log(_testTarget.FirstOrDefault(x => x.Value.Bar.MyVector.y > 40).Value.Bar.MyVector.y);
        }

        if (GUILayout.Button("First"))
        {
            Debug.Log(_testTarget.First(x => x.Key == "CCC").Value.Bar.MyVector.y);
        }

        if (GUILayout.Button("Take"))
        {
            Debug.Log(_testTarget.Take(10).ElementAt(0).Value.Bar.MyVector.y);
        }

        if (GUILayout.Button("Take while"))
        {
            Debug.Log(_testTarget.TakeWhile(x => x.Value.Bar.MyVector.x < 30).ElementAt(0).Value.Bar.MyVector.y);
        }

        if (GUILayout.Button("Skip"))
        {
            Debug.Log(_testTarget.Skip(4).ElementAt(0).Value.Bar.MyVector.y);
        } 
    }
}