Nina got a 86% on her science quiz. She got 43 questions correct. How
many questions were on the test? (What do you know, the part or the
whole?) *

50 problems total.   We know part of this, because it is possible there is extra credit.

Step-by-step explanation:

Normally if you get 100%, you get all the problems right.

So.

86% of (Total problems) = 43  correct

If you divide 43 by 86%, you can get the total number of problems.

Total problems = 43/0.86 = 50 problems

From your great MysticChaCha.  :-)

what i would say the best answer is a. 40.5