The analysis is as follows: From the meaning of the question, Xiao Xin ranks third from left to right, which means that there are five students in one row, and Xiao Xin ranks third from front to back, which means that there are also five people in each column of the team. So this team is a 5*5 team with 25 people.

Extended data:

Many places in life need to queue up, queue up to play games, queue up to buy things and so on. Common mathematical problems in queuing and their solutions are:?

(A preliminary understanding of the queuing problem in mathematics

1, drawing according to data.

(1) Draw a picture according to the information provided, and establish the relationship among formulas, pictures and text expressions.

For example, the following questions:

Penguins appeared, and the penguin captain was at the head of the team. The captain said, my team has eight athletes. queue up

The little penguin with the tail asks, how many penguins are there in front of me?

(1) Show the penguin dialogue with a picture or an expression.

(2) What does 8-1= 7 mean?

By creating situations, exerting independent creativity, designing various painting methods and establishing intuitive images with the help of painting, it is helpful to understand the meaning of the problem and pave the way for painting in subsequent teaching.

(2) Establish a model to solve the problem by drawing.

1. Establish the model of "missing number plus". Such as the following questions

(1) Little Nutbrown hare observed his position and found a math problem. It says: There are four animals on my left and six animals on my right. How many small animals are there?

Default: 10.

Default value: 1 1 piece.

Default value: 9.

Default: Use graphs to represent relationships.

Default: Use formula 4+6+ 1= 1 1 (only) to solve the problem.

Default: 4+7 or 5+6.

Introduce the meaning expressed by students with charts or formulas. Focus on answering the following questions.

① There is no 1 in the title. Add 1 to help students understand the meaning of the topic. Understand the meaning of the formula with charts.

Drawing can make complex problems intuitive and easy to solve.

2. Establish a "repeated subtraction" model

(1) Solve the zebra crossing queuing problem.

Zebra found a math problem: from the left, I ranked sixth, and from the right, I ranked third. How many small animals are there in our team?

Default value: 6+3+ 1= 10 (only)

Default value: 6+3=9 (only)

Default value: 6+3- 1=8 pieces.

(1) According to the above three situations, tell which method to solve the problem is correct.

(2) According to the correct diagram, and then reflect on the above three formulas, the solution ideas are the same as the diagram.

Through drawing, we can know more clearly that zebras are counted twice, so it is intuitive to subtract 1, add 1 or subtract 1.

(c) Discrimination of adding 1 and subtracting 1.

1, re-examine the question, and clearly need to add or subtract 1.

The above two questions. Both teams are required to have several small animals, but they are different.

Default: The topic has different meanings. The Tutu team said that "there are as many on its left as there are on its right", excluding Tutu, so it is necessary to add 1 to find the total; The zebra said, "Count from the left and count from the right." Zebras are counted twice, so you need to subtract 1 from the total.

Default: It is also clear in the picture that rabbits are missing, so 1 should be added, and zebra has calculated twice, and 1 should be reduced.

2. Solve problems independently.

(1) There are five chairs in the first row and 10 chairs in the second row. How many chairs are there in a room?

(2) There is a row of flowers, in which 1 pot is yellow flowers and the rest are red flowers. There are 6 pots of safflower around the yellow flower. A * * *, how many pots are there?

(3) There is a row of flowers, in which 1 pot is yellow flowers and the rest are red flowers. The yellow flower is the sixth pot from left to right. A * * *, how many pots are there?

By comparing and summarizing, analyze the differences between the two types of questions and deepen the understanding of the meaning of the questions.