0
votes
1answer
62 views

Is there a dash between “n-second” [duplicate]

Take the example "one-second interval". Is there a dash between "one" and "second"? Also, should second be plural if I say "three-second/s interval"?
2
votes
1answer
4k views

“40-50 years old” vs. “40-50 year olds” when referring to a group

In formal research, which is more correct, and why: the group of 40-50 years old OR the group of 40-50 year olds In any case the phrase in bold is to be treated as a noun only, as in: The ...