1. Decimal multiplication calculation method: calculate the product according to the law of integer multiplication; See how many decimal places a * * * factor has, and count the decimal points from the right side of the product.

2. Unit 2 Fractional Division

7. Calculation method of decimal divided by integer: decimal divided by integer, and then divided by integer. The decimal point of quotient should be aligned with the decimal point of dividend. The integer part is not divided enough, quotient 0, decimal point. If there is a remainder, add 0 and divide it.

Unit 3 Observing Objects

Observing objects from different angles, the shapes you see may be different;

4. Unit 4 Simple Equation

In the multiplication formula with letters, the multiplication sign in the middle of the letters can be recorded as ""or omitted. Multiply the letters and numbers and write the numbers before the letters.

5. Area of Polygon in Unit 5

Note: A set of quadrangles with parallel opposite sides is called trapezoid, in which the long side is usually called lower bottom and the short side is usually called upper bottom.