The total number of questions is uncertain. The part where A and B get the correct answer may be 1-7, but the wrong answer can be filtered out by other conditions.

Because the number of questions is an integer and the wrong number of A is 1/9, the total number of questions must be a multiple of 9.

Total number of questions = no problem *6= no problem *2*3

In other words, the number of correct answers should be a multiple of 3.

That's 3 or 6.

Three words

The total number of questions is 3*6= 18.

A got it right18-18/9 =16.

Six words

The total number of questions is 6*6=36.

That's right. 36-36/9=32

B failed anyway, hehe.