Incorrect Definition of "Latitude"

Chapter 4, Lab 1 defines latitude as

Latitude decreases in value as you move west

Latitude specifies the North-South position of a point on Earth. Longitude specifies the East-West position of a point on Earth. This is made even more confusing by the coordinate tuple not following the generally accepted convention of (latitude, longitude). The question should be rewritten as:

Longitude decreases in value as you move west.

How many trips in the sample_training.trips collection started at stations that are to the west of the -74 longitude coordinate?

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@Michael_Ruth1 you are most certainly correct. Good job bringing this up!

This confused me immensely, and I kept getting the incorrect answer because I was basing my calculations on the scientific version instead of the version portrayed in the lab.

Reference: Britannica, T. Editors of Encyclopaedia (2021, January 6). Latitude and longitude. Encyclopedia Britannica. latitude and longitude | Definition, Examples, Diagrams, & Facts | Britannica

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The solution to this problem, given by the author uses this dot notation path:

  {"start station location.coordinates": {
      "$lt": -74
    }
  }

but I solved it using this path(notice the 0 index next to the dot):

  {"start station location.coordinates.0": {
      "$lt": -74
    }
  }

So I wonder if “not mentioning the index” will implicitly default to zero(just as the author didn’t add the zero at the end)?
(Sorry that it is not directly related to this post, but I didn’t want to create a new post only for this question)

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Hi @Ader_Chox, thank you so much for pointing this out, I have escalated this issue to the appropriate channel. Please be rest assured that our team is working on it and we will try our best to fix it as soon as possible.
Meanwhile, if you have any doubts please feel free to reach out to us and we will be more than happy to help you.

Thanks. Regards.
Sourabh Bagrecha,
Curriculum Services Engineer.

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