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The deduction is a basic knowledge not only applied in mathematics but in most fields, until real life is still used. So what is the deduction called? How to help your baby master the knowledge when learning to eliminate effectively? Let Mầm non Cát Linh discover more clearly in the following article.

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What is subtraction?

In mathematics, subtraction is one of the 4 basic operations including plus, subtraction, multiplication and division. The elimination of the arithmetic will include 2 or more words to get the final result, which is the original element reduced by the element being deducted.

The deduction symbol is “-“.

For subtraction commonly used for natural numbers, fractions, decimal numbers, integers, complex numbers and real numbers. A subtraction calculation will be made up of: A – B = c.

In there:

• A is the subtracted number

• b is the minus number

• c is the brand

The condition for performing the main deduction is that the number of deductions must be greater than or equal to the minus. When performing the calculation of 2 natural numbers, we only need to follow the order from right to spread. To make sure the results, we perform the signal calculation plus the minus, if the result is the deductible number, the calculation is accurate.

For example: 15 – 8 = 7. Check out the exact results, then we take 7 + 8 = 15.

Properties of subtraction

In mathematics, the subtraction has the following properties:

• The except for that itself: AA = 0
• Except for 0: A-0 = a
• The difference of the minus for 0 is equal to that.

Common forms of minus math

Similar to the addition, in the except calculation, there will also be 2 forms that except remember and do not remember. Specifically:

The deduction does not remember

The deduction does not remember is the basic math, when we perform the calculation from right to left in rows with the number of deducted larger than the minus number.

Example: 67 – 15 = 52

In there

• Number 67: Called the subtracted number.

• Number 15: Called the minus number.

• Number 52: The result of the except for the name is called the difference.

Remember

Remember that the deduction is more advanced but also done in order from right to left, but in the same row of deductions smaller than the number except we will have to borrow 1 in the next row to subtract (remember 1). Until when performing the subtraction in the next row we add 1 in the minus to calculate.

Example: 35 – 17:

Unit row: 5 Unable to deduct 7, take 15 minus 7 equal to 8, write 8 remember 1.

Tens: 1 plus 1 equal to 2, 3 minus 2 equals 1, writing 1. The result is 18

Types of exercises related to common subtraction

For babies who have just started studying with subtraction, they will get acquainted with the following basic forms:

Form 1: Perform calculation

With this form of math may be mental or calculated and calculated. The baby’s task is to perform the calculation of subtraction from right to left to find the correct answer.

Example: Calculate mental 34 – 12 = 22

Form 2: Solving math with words

Solution: First, they will have to read and analyze the problem carefully for the data, the quantity decreases or increases, the problem is given. Then based on the keywords of the article such as searching “remaining”, “all”, … and the requirements of the problem to determine the appropriate calculation.

Next will have to present the solution, calculation and write the correct answer. Finally, you will have to check the problem and results.

For example: Mom went to the market to buy 10 apples, she gave 3 fruits, gave 2 fruits. Ask Mother a few fruits.

Solution:

The remaining mother of apples is:

10 – 3 – 2 = 5 (fruit)

Answer: 5 fruits.

Form 3: Find the missing number in subtraction

Solution method: They will also have to perform calculations from left to right. If the minus operations have 3 values, the problem indicates two of the 3 values, then we will calculate to find the missing value.

For example

5…. – 13 =… .2

Prize:

Mental from the unit to tens of

• Unit row: Which number deducted with 3 equals 2. We have: 5 – 3 = 2 so the number found is the number 5.
• Tens: mental 5 – 1 = 4 so the number to fill in the remaining space is 4

So fill out the numbers in the blank to be calculated as follows:

55 – 13 = 42

Form 4: Find x

Solution: We will have to determine the role of X to find as the deducted number, the minus number or the difference to apply the rule to find an unknown number that “want to find the term unknown to take the sum of the known term or want to find the quantity, we take the minus minus number.”

Example: x – 7 = 15

x = 15 + 7

x = 22

The secret to helping children learn, memorize and apply knowledge about effective subtraction

To help the mathematical learning process in general, the calculation of minus with the baby is easier and more effective, parents can apply the following tips:

Learn math by positive methods with Mầm non Cát Linh Math

Mathematics is a subject with numbers, dry calculations, so to make your child’s learning process more interesting, parents can choose Mầm non Cát Linh Math to accompany the baby. With positive teaching methods through games, interactive activities, videos and rough movement will be more interested in this subject.

Specifically, Mầm non Cát Linh Math is the application of English math teaching with the content of the new education program, based on the development of capacity instead of transmitting knowledge as the Ministry of Education and Training sets. Therefore, the moments of learning math with Mầm non Cát Linh Math will be fun but still make sure your baby understands and practices accurately.

Here, before the baby starts the lesson will be able to watch the cartoon video instructions in advance so that they can understand the knowledge. The baby will then participate in interactive activities on the application to see what they understand about the lesson, review and practice with the knowledge learned through many different interesting experiences.

Finally, the baby will be mobilized and sperm with the supplementary exercise book that Mầm non Cát Linh provides. Thereby children will be able to participate in interesting learning activities that have just developed evenly knowledge, emotions and skills to help learning to achieve better results.

https://www.youtube.com/watch?v=7dsjpvhfros

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Get acquainted with simple things

For children starting to learn math will often face many difficulties, they are easy to “learn first and after” as well as they are easy to hate things that are repeated as high as they learn to subtract. So parents need to be really patient in teaching children to learn.

Therefore, instead of forcing children to study them, parents should give them approaches to this knowledge gently, from simple things such as helping children see the value of subtraction operations, encourage children with rewards, join children to participate in math games, … This will help children feel more ready and excited when learning.

Learning daily context

Instead of teaching children to learn to calculate minus on books, parents can help children learn through daily contexts such as calculating objects in the house such as the number of candies, dishes, counting toys, … Initially, when studying should make subtraction in small quantities before, until they understand and get used to increasing the level of calculation.

Use tools to support teaching mathematics

To increase visuality, imagine children to understand except parents can use familiar objects as a support tool. For example, parents can offer 10 balls, giving them 4 capsules to ask how many parents are left. This will be able to understand the deduction more intuitively.

In addition, parents should also encourage children to think and imagine when learning math more. For example, with subtracts, let your baby imagine in a forest with 5 horses, 2 children run out, the left …

Change of study form

Instead of just learning to deduct on books, parents should diversify the method of teaching children to learn from the Mầm non Cát Linh Math application, learn through games, puzzle, practice, … so that they will not be bored. If practicing deduction by sticks, cards, .. but the child starts to get bored, parents should try limiting the study time with interactive activities to help change the atmosphere to help children learn more excited.

Do not forget to practice often

Besides grasping the nature of subtraction, parents should also ask the baby to do regular exercises. In addition to the exercises on the school, you can also collect many different types of exercises to try and practice regularly, help your child learn to understand and avoid forgetting knowledge.

Summarize some subtraction exercises for children to practice

Here are some subtraction exercises for your baby to practice:

Lesson 1: Set calculated and calculate

a. 60 – 5 b. 58 – 9 c. 50 – 4 d. 15 – 8 e. 60 – 27

f. 30 – 14 g. 40 – 15 g. 90 -43 h. 80 – 22 i. 60 – 17

Lesson 2: Write the appropriate number in the blank:

Lesson 3: Calculation:

60 – 10 – 30 = …. 20 – 7 – 3 = …..

100 – 20 – 40 = ….. 5 – 5 – 18 = …..

25 – 5 – 12 = ….. 52 – 2 – 17 = …..

73 – 3 – 44 = ….. 48 – 8 – 26 = ….

Lesson 4: Fill in the seal>, <, = in the dot

60 …….. 93 – 26 59 …….. 72 – 19

33 …….. 61 – 28 68 …….. 68 – 0

Lesson 5: Flowers have some balloons. Flowers give flowers more 5 more fruits, flowers have even twenty fruits. Ask how many balloon flowers at first?

Lesson 6: The total age of 2 father and son is 40 years old. This year I am 7 years old. Quiz you know how old is your father now?

Lesson 7: Coffee candy and coconut candy package are all 90. Ask:

A. How many coffee candy packages have?

B. How many candies must be reduced in the package of coffee candy so that the number of candies in 2 packages is equal?

Lesson 8: Summarize with the following problem diagram and solve:

Ms. Lan bought a book of 50 thousand dong. Lan bought books less than Lan 15 thousand dong.

A. Calculating the amount of money to buy books?

B. How much do you both buy books?

Lesson 9: The first tank contains 865l of water, the second tank contains less than the first tank 200l of water. How many liters of water contain the second tank?

Lesson 10: Find x:

a) x – 4 = 8; b) x – 9 = 18;

c) x – 10 = 25 d) x – 8 = 24;

e) x – 7 = 21; g) x – 12 = 36.

Conclude

Above is the basic knowledge about subtraction. This is considered a fundamental calculation to learn higher math knowledge, as well as practical applications. So parents can apply the above sharing of Mầm non Cát Linh to make your baby’s learning more effectively.

References

Subtract – Definition with Examples

https://www.splashlearn.com/math-vocabulary/subtraction/subtract

Subtraction

https://www.cuemath.com/numbers/subtraction/

Nguồn: https://mncatlinhdd.edu.vn/ Tác giả: Nguyễn Lân dũng