Research problems in the Math field. You can do this in any number of ways: look at professional journals, check the news.
Find a peer-reviewed research article related to that problem and describe it.
Your post should include:
A description of the problem and why it matters.
A summary of the article in less than 100 words
A description of your intended audience. It is impossible to be too specific on this one — it could even be an individual with some kind of authority.