From page 8 to page 29, the calculation method is 29-9+ 1 = 2 1.

1 is added to add page 8.

Multiplication:

(1) How much is it?

(2) How many times is a number;

③ Find the area and volume of the object;

(4) Find the fraction or percentage of a number.

Department:

(1) divide a number into several parts on average and find one of them;

(2) How many other numbers are there in a number;

(3) What fraction or percentage of a number is known to find this number;

(4) Find a number that is several times that of another number.