(1) If the test score is an integer.
Then, suppose Xiaohui is 6 years old (the average pupil is at least 6 years old), ranking first, and the score is not an integer, which is too big (39 16 divided by 1 divided by 6), so it is excluded; Suppose it is the second, the score is too big to be realistic, and it is ruled out. The following answers in a similar way in turn and find a reasonable answer.
Xiaohui was 7 years old. , 8, 9, 10,1,12, 13 (generally, the maximum age is 13), and similar methods can be used.
(2) If the score is decimal.
Then, the method is similar to (1), which can be solved by exhaustive method. I hope you can learn this way of thinking.
This kind of thinking is also very helpful for you to attend the interview in the future. Sometimes, some problems, what matters is not the result (because some problems have no result). Mainly examine your views and thoughts on this issue. This kind of thinking will also help you to participate in the competition and creation of mathematical modeling in the future.
Come on, class.