1, three digits should be aligned with two digits, and ten digits should be aligned with ten digits.

2. First, multiply each bit of three digits with each bit of two digits respectively.

3. Multiply the ten digits of two digits with each digit of three digits respectively, and the digits of the multiplication result should be aligned with the ten digits of the previous result.

4. Then add the two results to get the result of multiplying three digits by two digits.

Data expansion:

Vertical calculation refers to a vertical calculation in the calculation process, which makes the calculation simple. In addition calculation, the same numbers are aligned. If the sum exceeds 10, it will move forward to 1. When subtracting, the same numbers are aligned. If it is not enough, borrow 1 from the last digit as 10.

"Vertical" means that each transition number is changed from the previous transition number, and then the single digits of the previous transition number are multiplied by 2. If carry is needed, advance 1, then increase the unit number by ten digits, and so on, and add the new operand to the unit number.

Longitudinal formula refers to a longitudinal formula in the calculation process, which makes the calculation simple. Vertical calculation refers to a vertical calculation in the calculation process, which makes the calculation simple. In addition calculation, the same numbers are aligned. If the sum exceeds 10, it will move forward to 1. When subtracting, the same numbers are aligned. If it is not enough, borrow 1 from the last digit as 10.

Some parents and teachers hold a negative attitude towards vertical calculation, thinking that it is an outdated calculation method. In fact, vertical calculation is not out of date, it is a very practical calculation method. In modern society, although we can use calculators and computers to calculate, vertical calculation is still an important calculation method, which can make children better understand mathematical concepts and improve their calculation ability and thinking ability.

Vertical calculation of primary school mathematics is an important part of children's mathematics learning, which can cultivate children's mathematical thinking and calculation ability and improve children's attention and patience. Therefore, parents and teachers should pay attention to vertical calculation, so that children can better master this practical calculation method.