There are 20 questions in the math contest. Every time you do a problem correctly, you get 5 points. If you do a wrong question, you will get 1 point. Xiaohua got 76 points. Ask Xiaohua to do a few questions correctly. Assuming Xiaohua has done everything right, he should get:

20×5= 100 (minutes)

But he actually got 76 points, which is different from the hypothesis:

100-76=24 (point)

After changing the correct topic to the wrong one, not only will you not get 5 points, but you will also be deducted 1 point. One question is missing:

5+ 1=6 (points)

So the number of error questions is:

24÷6=4 (topic)

The correct number of questions is:

20-4= 16 (theme)

A: Xiaohua got it right 16.

Check:

Do the right question * * * Score:

16×5=80 (point)

Deduct points for doing wrong questions:

4× 1=4 (points)

Total score:

80-4=76 (point)

Match the question and the answer is correct.

PS: This is a typical chicken and rabbit cage problem.