Endless decimal
A decimal with a finite number of digits after the decimal part. For example, 3. 1465, 0.364, 8.32 18798456, etc. All finite decimals belong to rational numbers and can be converted into component numbers.
A simplest fraction can be converted into a decimal finite fraction if and only if its denominator contains only prime factors 2 or 5 or both. Similarly, a simplest fraction can be transformed into a finite fraction of the base of a positive integer if and only if the prime factor of its denominator is a subset of the prime factor of the base.
Endless decimal
repeating decimal
A number or numbers that start from somewhere in the decimal part and appear repeatedly in turn are called cyclic decimals. Such as1/7 = 0.142857142857,1/6 =1.83333, etc. Cyclic decimals also belong to rational numbers and can be converted into component numbers.
Infinite non-repeating decimal
There are infinitely many numbers in the decimal part, and the decimal with one or several numbers that do not appear repeatedly in turn is called infinite acyclic decimal, such as pi = 3.14159265358979323 ..., and the base of natural logarithm e = 2.71828182823. Infinitely cyclic decimals, that is, irrational numbers, cannot be converted into component forms.
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.
Decimal attribute
Add or delete any zeros at the end of the decimal, and the size of the decimal remains the same. For example: 0.4=0.400, 0.060=0.06.
Move the decimal point to the right (or left) by n bits respectively, and the value of the decimal point will be expanded (or reduced) by n times.
Divide a whole into several parts on average, 100, 1000 ... such 1 parts are tens, percentages and thousands ... such scores can be expressed in decimals.
For example, three tenths can be written as decimal 0.3.
Decimals are divided into positive parts, decimal points and decimal parts:
Decimal numerical sequence table
Decimals represent tens, percentiles represent one percent, and thousandths represent one thousandth. ...
For example, in 0.265, 2 means two 0. 1, 6 means six 0.0 1, and 5 means five 0.00 1.
Decimal reading: the integer part of decimal is read by integer, the decimal point is read, and the decimal part reads each number from left to right.
For example, 12.5 is pronounced as 12.5.
1230.603 is pronounced 1230.603.
The digits to the right of the decimal point can be called decimals.
For example, 12.36 is two decimal places.
0. 123 is a three-digit decimal.
0. 1 is a decimal place.
Properties of decimals:
Add 0 or delete 0 at the end of the decimal, and the decimal size remains the same. Such as 0. 12=0. 120.