translation - Expressing "the nth person to 〜"

I would like to express the following in Japanese:

You are the third person to ask me that.

You were the first person to greet me yesterday.

If I attempt to translate, I end up with:

３番目にそれを聞いた人は◯◯さんです。

昨日初めて挨拶してくれたのは◯◯さんです。

〜番目に〜したのは〜

However, I am not sure if this is the best way to express this.

More concretely:

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  Are these sentences grammatically correct?

  
  
  


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  Do these sentences convey what I am trying to convey?

  
  


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  Are these sentences natural? If not, how might I express these ideas more naturally? If so, are there other natural ways of expressing them?

  
  

Answer

Your sentences are correct grammatically.

Do you know a word ''３人目'', which is pronounced sannimme. This word means the third person, it is usually used more than ''３番目の人''.
You can say the fact in three ways as follows.
By the way, ''聞いてくる'' is often used when someone asks ME, so I used it in examples.

A. ３人目にそれを聞いてきたの (or 人)は、○○さんです。
B. それを聞いてきたのは、○○さんが３人目です。
C. ○○さんは、それを聞いてきた３人目の人です。

It depends on what information you want to be the subject or what is the common knowledge.

When you mention the person who asked it to you in the third, you would say A.

When you mention the persons who asked it, you would say B.
When you mention the person called ○○, you would say C.
Likewise, you can say as follows.

α. 昨日初めて挨拶してくれたのは、○○さんです。
β. 昨日挨拶してくれたのは、○○さんが初めてです。
γ. ○○さんは、昨日初めて挨拶してくれた人です。

If you have some questions, I will answer to them for a comment, as far as I can.