Ok so we know that the student scored 86%, but missed 33 problems. That means those 33 problems were worth 14% of the total mark, as the would've scored 100% if they scored those as well.
This means that one percent is equivalent to
[tex] \frac{33}{14} questions[/tex]
Which is about 2.357 questions.
Therefore all the questions (which is 100%) is
[tex] \frac{33}{14} \times 100[/tex]
Which is 235.71 questions, rounded up to 236 questions.
So there were 236 problems in the test
Hope this helped
