First, we distinguish two concepts: average score 1 1 average score 12. These two concepts should be distinguished in the title.
Secondly, I have to think about it. What is the average score? How to calculate? (Everyone generally uses the formula of total score/total number of people = average score). Here we want to use another method to calculate: that is, more action and less compensation. (If A has scored 6 points, it has already scored 4 points. If A with more points is moved to 1 to B, the average score of two people can be obtained. The average score of two people can be 5 points. )
Now start to solve the problem:
Wang Ming's make-up exam score is 5.5 points higher than the average score of 12. This condition tells us that Wang Ming's score is higher than the average score of the former 1 1, that is to say, after the score of A is added to the total score, the average branch of the former 12 will increase a little.
If we start with the total score at this time, then I won't solve it. The equation doesn't seem to be suitable for us primary school students. Then we will solve the problem by moving more and making up less, and it is most important to understand the meaning of the problem.
How did you get the average score of 12 people? Wang Ming first reserved an average score of 12 people, and then divided the extra score into 1 1 to make up 1 1 people respectively. Think clearly about the title of this sentence. )
Wang Ming's make-up exam score is 5.5 points higher than the average score of 12. "There are 5.5 points here" is the key to solving the problem. This 5.5 points is higher than the average score of 1 1 person.
5.5 ÷ 1 1 = 0.5.
Then the average score of 12 people is: 85+0.5 = 85.5 points.
Ask Wang Ming's score again: 85.5+5.5 = 9 1.
(If you don't believe me, you can test the numbers in the original question. )