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The decimal number is one of the special numbers, there will be equal calculations similar to the natural number. So, to better understand the decimal? What types of math problems are there? Let’s discover more in detail in the following article with Mầm non Cát Linh.
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What is decimal?
The main decimal numbers are numerical fractions and samples. In particular, the main number is the numbers in the form of 10, 100, 1000 … the main form is the product of the numbers 10.
The decimal is usually written as a monk: 0.1; 0.001; 0.0001 …
How to read decimal numbers
How to read decimals we will rely on the formula: the whole part + the “comma” + the decimal part.
For example:
- 3, 45: Three commas for annual
- 30.82: Thirty and eighty -twenty -two.
Decimal structure
The decimal is composed of 2 parts, the integer and the decimal and they are separated by the comma. In particular, the numbers before the comma called the whole part, after the comma is the decimal part.
The ways are converted into decimal
When learning about decimals, there will be a form of conversion of decimal numbers to other numbers. Include:
Convert fractions into decimal numbers
To convert fractions into decimal numbers, we only need to take the number divided by the denominator. In addition, it is possible to convert decimal fractions and then convert it into decimal numbers, by multiplying both death and samples for a natural number to have samples of 10, 100, 1000 ….
* Note: When converting decimal numbers into decimal numbers, we need to count how many zeros that form is, the decimal part of the decimal will have so many digits.
For example, converting fertilizer 6/5 into decimal numbers.
Convert mixed numbers into decimal numbers
To convert the mixture into decimal numbers, we will change the number to the decimal fractions and then convert it into decimal numbers.
Convert measurements of length and mass into decimal numbers
First, we need to find the connection between the two units of mass measurement or the given length measurement unit. Then convert them into decimal fractions with larger units, then continue to convert into the corresponding decimal form.
Example: Change 5cm to DM
Convert decimal into decimal fractions
To convert a decimal to decimal, we follow the following steps:
- Step 1: Determine the decimal part of the given decimal.
- Step 2: Write the denominator of the corresponding fraction of 10, 100, 10000 … with zero numbers will be equal to the number of digits in the decimal section.
For example, convert decimal 5.43 to decimal fractions.
Solution:
The decimal part of the decimal of 5.43 has 2 digits. So the decimal number must have a sample of 100. Equivalent to 4.43 = 543/100.
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The calculations with decimal numbers
Similar to other types of numbers, in decimals will also have basic forms and solutions as follows:
Add decimal
In the addition of 2 decimal numbers, we follow these steps:
- Step 1: Write this term below the other so that the digits are in the same row when calculated in the vertical column.
- Step 2: Carry out the plus calculation as plus natural numbers.
- Step 3: Place the comma in the sum of the column with the comma of the terms.
For example: 45, 08 + 24, 97 =?
We set the calculation and do the following:
Besides, you should also refer to how to perform a fractional addition to be able to do the transport exercise right below.
Decimal subtraction
Similar to the addition of addition, in the deduction of decimal numbers, we also write the number subtracted below the number of deductions so that the digits in the same line are placed straight. The subtraction will then be performed as subtracting as subtracted by the natural number and the comma at the signal signal with the comma of the subtraction and the deductible number.
For example: 68, 4 – 25, 7 =?
* Note: If the number in the decimal part of the number is subtracted less than the number of digits in the decimal section, we can write the zero digit to the right of the decimal part of the deductible number, and then subtract the same as the usual natural number.
Example: 45, 8 – 26.54 =?
Multiplication of decimal numbers
For multiplication of decimal numbers, we will divide into many cases as follows:
Case 1: multiply a decimal with a natural number
To multiply the decimal number with natural numbers, we follow the following steps:
- Step 1: Conduct multiplied as natural numbers.
- Step 2: Count the decimal section of the decimal number how many digits, then set the plaque at the trace of the trace from the number of digits from right to left.
For example: 6.8 x 15 =?
We set the calculation and do the following:
Case 2: multiply a decimal with 10, 100,1000, …
To multiply the decimal numbers with numbers 10, 100, 1000 … we only need to transfer the comma of that number to the right of 1, 2, 3 … digits.
For example:
1.5 x 10 = 15
0.912 x 100 = 91.2
4.32 x 1000 = 4320.
Case 3: multiply a decimal with a decimal
In order to multiply the decimal numbers with other decimal numbers, we also perform the same multiplication as the natural number. Then, count in the decimal section of the two factors there are many digits, then set the plaque in the product that many digits turn from right to left.
Example: 25.6 x 1.5 =?
We set the calculation and do the following:
Decimal division
Similar to multiplication, with the division of decimals will also divide into the following cases:
Case 1: Divide a decimal to a natural number
To divide the decimal number by the natural number, we proceed to divide the integer part of the number divided by the division number. Then put the comma on the right of the injury that was found before taking the first digit in the decimal part of the divided number to continue the division. Finally, perform the division with each digit in the decimal section of the soda.
For example: 216.72: 42 =?
We set and do the following:
Case 2: Divide a decimal for 10, 100, 1000 …
To divide the decimal numbers for the numbers 10, 100, 1000 … we only need to transfer the comma of that number to the left 1, 2, 3 … digits.
For example:
43, 2: 10 = 4, 32
12.5: 100 = 0.125
2543.6: 1000 = 2,5436
Case 3: Divide a natural number for a natural number that Thuong found is a decimal
When solving the division of a natural number for the remaining natural numbers, we make the division continue as follows:
- Write a comma corresponding to the right side of the trade.
- Write the right of the one -digit balance to the right of the number 00 and then continue to divide.
- If there is another leftover, we write the right to the right of the new number 00 and continue to divide until the remainder is 0.
Example: 483: 35 =?
We set the calculation and do the following:
Case 4: Divide a natural number for a decimal
To divide the natural number by decimal, we need to count in the decimal section of the division number how many digits will add on the right of the right number that is divided by 0.
Example: 3: 6.25 =?
We set the calculation and do the following:
Case 5: Divide a decimal by a decimal
To divide the decimal number by other decimals, we also count the number in the decimal section of the division number how many digits, then transfer the comma at the number divided to the right of so many digits. Then continue to put the comma in the division number and perform the division similar to the natural number.
For example: 91.08: 3.6 =?
We put the calculation and then do the following:
Compare decimal numbers
To be able to compare two decimal numbers, we follow these steps:
- Compare the integer part of the two decimal numbers as two natural numbers, which part of the decimal is larger, the number is larger.
- If the integer part of the two decimals is equal, we compare the decimal part from left to right. Coming to the same row, which decimal numbers have the same number in the same large row, the number is larger.
For example: Write the decimal below in order from childish to large: 7.34; 6.42; 5.98; 7.43; 6.01
Solution:
Conducting comparison of the whole part, we see 5 <6 <7
Continue to compare 2 numbers with the same integer, we have: 7.34 <7, 43 and 6, 01 <0, 42
Inferred, the decimal sequence has been arranged in order from childish to large as follows: 5.98; 6.01; 6.42; 7.34; 7.43.
Exercise on decimal associated instructions
Below Mầm non Cát Linh will summarize some exercises on decimals, so that they can monitor and practice together:
Tips to learn effective decimal knowledge
To improve the effectiveness of solving exercises on decimal numbers, here are some tips that parents and children can refer to:
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Understand the theory of decimal numbers: To solve the exercise, requires the children to master the theory of decimal from reading, writing, structure, calculations, ways of switching … This is the most important foundation. If your baby forgets or does not understand somewhat, parents need to promptly guide and strengthen their children.
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Learning with the practice: In addition to learning theory, parents should encourage their children to practice more often through doing homework, textbooks, learning more knowledge on the internet, exam preparation … that is the method to help stimulate the ability to remember, absorb and think better.
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Learning mathematics applied to reality: Application of decimal numbers in reality is quite a lot such as measuring distance, volume of objects, length of objects … So, parents can give related examples to help children easily visualize and memorize this knowledge better.
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Building a platform and love to learn math with Mầm non Cát Linh Math: This is an online mathematical teaching application for preschool and elementary children. With the content of more than 60 math themes, including decimal, taught in the form of videos, funny animations that help children easily absorb and memorize knowledge. Along with that, the baby is also practiced through personalized interactive games, helping to increase the ability to understand, remember and think when learning math and solving problems in life better. Along with many features that support the learning of the baby’s math, parents’ management are integrated on Mầm non Cát Linh Math. With only 2000 VND/day but the effect that this application brings is great that parents can refer to.
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Conclude
Above is a summary of the basic knowledge about detailed decimal numbers. Hopefully, based on the above information, it will support their learning more easily, as well as helping the teaching of parents are also more leisurely but the effect is high.
References
Decimal – Introduction
https://www.splashlearn.com/math-vocabulary/decimals/decimal
What is Decimal?
https://www.techtarget.com/whatis/definition/decimal
Decimal
https://en.wikipedia.org/wiki/decimal
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