Expression: "Prince William has lost a tremendous amount of hair."

[Tom]

Hi

Which one of the folowing sentences is correct and natural?

[Yankee]

Hi Mr. Archer :D

Yes, I'd use the word 'amount'.
I would NOT use the word 'number'.

(If I were permitted to categorize things as 'correct' or 'incorrect' on this site, I would categorize the use of the word 'number' in that sentence as incorrect.)
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