Proposal: Math Challenges
Must the asker already know the answer to their problem?
Or can one ask puzzles not knowing the answer?
One of the foundations in creating this site is precisely what you're asking, and the answer is yes. Otherwise it would be no different to MSE, where genuine questions are asked by askers who don't know the answer to them.
Beware though, by 'puzzles', we don't want questions like 'Solve this Sudoku' or 'Make 34 using these four numbers' as they are already allowed on Puzzling. As little overlap as possible is desired.