Answer:
Karen missed 9 of the 45 questions on her mathematics exam. The exam had a total of 45 questions.
Explanation:
If Karen missed 9 questions (which equals 20% of the exam), then she completed 80% of the exam.
9 questions = 20%
80% = x
To solve this, we can divide the number of questions missed (9) by 20%, which equals 45. Thus, Karen's test had a total of 45 questions!