See these three pages:
All three of them say:
Earned at least X total score for at least 20 answers in the c# tag.
This same text also appears on the tooltip for the tag badge:
Also note the double colon after 'gold badge'
As well as on these pages:
But the badges page clearly states:
- Bronze Badge: You must have a total score of 100 in at least 20 non-community wiki answers to achieve this badge.
- Silver Badge: You must have a total score of 400 in at least 80 non-community wiki answers to achieve this badge.
- Gold Badge: You must have a total score of 1000 in at least 200 non-community wiki answers to achieve this badge.
Edit:
It has been noted in the comments that other users see different numbers in these pages, but in all cases it appears they see the same number of answers are required for all tag badge description, regardless of the badge's type.