1. No few students were present at the meeting.

2. Not a few students were present at the meeting.

3. Quite a few students were present at the meeting.
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Are they all the same in meaning?

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4. I have no little money.
5. I have not a little money.
6. I have quite a little money.
7. I have a lot of money.
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Do they have the same meaning? Does #4,5, or 6 mean #7?

1 doesn't make sense.

2 means that many students (not a few) were present, but this is very awkward phrasing.

3 is the common expression and means that many students were present.

4, 5, and 6 are incorrect.
7 is correct.