Answer: 72
Explanation:
From the question, we are informed that Mary Beth needs a 90% on her final exam to get an A for the quarter and that the exam has 80 questions.
The number of questions does that Mary need to answer correctly in order for her to get an A would be 90% of 80. This will be:
= 90% × 80
= 90/100 × 80
= 72
She must get 72 to get a A.