Answer:
Let's start by using a proportion to find the total number of questions on the test. We know that Charles answered 23 questions correctly and received a grade of 92%, which means he missed 8% of the questions.
Let x be the total number of questions on the test. Then 8% of the questions that Charles missed can be expressed as 0.08x.
The number of questions that Charles answered correctly plus the number of questions he missed must add up to the total number of questions on the test:
23 + 0.08x = x
Simplifying and solving for x, we get:
0.92x = 23
x = 23 / 0.92
x ≈ 25
Therefore, the total number of questions on the test was approximately 25.