For example, n small houses need (n- 1)×4+5=4n+ 1, and when n= 15, sticks are needed: (15- 1) × 4+5 = 665438.

A: It takes 6 1 stick to build 15 houses. 89 sticks can build 22 such houses. Surrounding a rectangle or square with wooden sticks is a topic in the first volume of the third grade of primary school. Students can practice through application problems.

Application and calculation skills of mathematical stick

Small stick formula: If the number of sticks is divided by 2, the number will be divided into the sum of two numbers, with Mahayana stick length as the length and Mahayana stick length as the width. The length-width difference is large and the area is small, and the length-width difference is small and the area is large.

The reason why the number of sticks is divided by 2, that is, divided by 2, is because the number of sticks is divided into one long and one wide, and there are several sticks. Then 20÷2= 10 (root), this number is divided by the sum of two numbers, the large number is the long stick root, and the decimal number is the wide stick root. Mahayana sticks are long. Why is the length of Mahayana stick long? Because the length of the stick is not 1cm, 1dm, 1m per question.