I have seen people write 'a twenty-minute walk', which is deemed correct.
Then, if it is a 25-minute walk, people tend to write it as ' a twenty-five minute walk' rather than 'a twenty-five-minute walk'.
My question is:
Which is a more academically acceptable way of the two:
a twenty-five minute walk or a twenty-five-minute walk ?
Why would you drop the hyphen just because it now has two words?
A twenty-minute walk
A twenty-five-minute walk
In many style manuals, numbers over 10 are written as numerals.
A 20-minute walk.
A 25-minute walk.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.