I've loaded ASCIIMathML as per instructions here, in meta.php in the theme folder. Works fine in the question body. However, Moodle won't accept the answer as numerical in answer fields.
The answer is a fraction. It will not accept `13/20` or 13/20.
I am using numerical_question_type. Fractions can be displayed, but I can't enter a fraction as an answer. It wants an integer or float. Is there any way to accept a fraction answer?
I'm afraid there is no way to do it without rewriting the code of that question type.
The point is that division (slash) is an operation like addition, subtraction or multiplication, they are not parts of a number and can't be used in an answer that must be a number.