Comparing the size of decimals with three times is based on the preliminary understanding of decimals, and comparing the size of decimals with four times is carried out after learning the meaning and properties of decimals and the addition and subtraction operations of decimals, which is complicated and involves the process of addition and subtraction together.

decimal

Decimal is a special expression of real numbers. All fractions can be expressed as decimals, and the points in decimals are called decimal points, which are the dividing lines between the integer part and the decimal part of a decimal. Decimals with zero integer parts are called pure decimals, and decimals with non-zero integer parts are called decimals.