Ask HN: Is there a software model that can generate math questions?

Which kind of math questions?

* If a book and a pencil cost $10 and two books and a pencil cost $17, how much does a pencil cost?

* What are all the subgroups of a group or order 50?

* Integral(x * e^x dx) ?

The more complex aptitude ones that require use of theorems and stuff. Questions that are used for competitive exam preps.