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C# Querying With LINQ Query Operators Aggregates

What's the correct code look like? I have less than 24hours to figure this out and pass, new so please give solution

confused on where to begin, please give actual answer, Im ok with being told and learning from that.

CodeChallenge.cs
var myBirds = new List<Bird> 
{ 
    new Bird { Name = "Cardinal", Color = "Red", Sightings = 3 },
    new Bird { Name =  "Dove", Color = "White", Sightings = 2 },
    new Bird { Name =  "Robin", Color = "Red", Sightings = 5 }
};

var yourBirds = new List<Bird> 
{ 
    new Bird { Name =  "Dove", Color = "White", Sightings = 2 },
    new Bird { Name =  "Robin", Color = "Red", Sightings = 5 },
    new Bird { Name =  "Canary", Color = "Yellow", Sightings = 0 }
};

var ourBirds = myBirds.Join(yourBirds,
                            mb => mb.Name,
                            yb => yb.Name,
                            (mb, yb) => (mb));

var sumOfSightings = ourBirds.Sum(ob => ob.Sightings);
var averageSightings = ourBirds.Sum(ob => ob.Sightings);

1 Answer

Jennifer Nordell
seal-mask
STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi there, Ulyssa Sneed! It looks like you're doing really well and got the .Sum just fine! The average is going to be almost exactly the same. In fact, the only difference between the two is that you will use the .Average aggregate method instead of the .Sum method.

var averageSightings = ourBirds.Average(ob => ob.Sightings);

You can see where the instructor introduces the .Average method at around 3:18 of the preceding video.

Hope this helps! :sparkles: