When talking about a quantity of people or things, I get 2 phrases "in number" and "in numbers". It's a little bit confusing for me, so I ask for help. These are some examples I got from online dictionaries
- We were eight in number(= there were eight of us).
- Letters of complaint were surprisingly few in number (= there were not many of them).
- The protesters were few in number, but they were very loud.
- Nurses are leaving the profession in increasing numbers.
- Newspapers are produced in vast numbers.