1、 120x3=、200x4=、30x50=、400x6=、50x70=、600x8=、70x90=、800x 10=、90x 100=、 12x40=、7 10x50=、3 100
2、 150x30=、90x450=、70x920=、940x50=、760x30=、6 10x20=、 10x40=、920x30=、6 10x60=、4 10x40=、20x 10x 40
3、3 10x70=、8 10x70=、520x70=、3 10x20=、340x50=、70x640=、870x60=、760x40=、990x30=、770x40=、 120x70=、420x90=、65430
Multiplication is a shortcut to add up the same numbers. The result of its operation is called product, and "X" is the symbol of multiplication. From the philosophical point of view, multiplication is the result of qualitative change caused by additive quantity. The multiplication of integers (including negative numbers), rational numbers (fractions) and real numbers is a systematic summary of this basic definition.
Multiplication can also be seen as calculating the objects arranged in a rectangle (integer) or finding the area of a rectangle with a given side length. The area of the rectangle does not depend on which side is measured first, which shows the exchange property. The product of two measured values is a new type of measurement, for example, multiplying the length of two sides of a rectangle to get its area, which is the theme of size analysis.
Multiplication is one of the simplest operations in arithmetic. It originated from the multiplication of integers. The 99-99 multiplication melody is also often called "Little 99". The formula for students to learn "elementary ninety-nine" is from "11" to "998 1", while in ancient times, it was the other way around, from "998 1" to "224".
Calculation method of multiplication
First of all, multiplication is a basic mathematical operation used to calculate the product of two or more numbers. In multiplication, multiplicand, multiplier and product are respectively expressed as: multiplicand × multiplier = product.
Secondly, the calculation of multiplication is based on the formula of multiplication. When the columns are vertical, the same numbers should be aligned. Starting from the unit, multiply each number of the second factor by the first factor, and the number will be aligned with the number of the second factor. Finally, add up the products multiplied by several times.
In addition, if one number is expanded several times and another factor is reduced to a fraction of the original, their product remains unchanged.