The four operations in mathematics in the fourth grade of primary school refer to the four basic operations of addition, subtraction, multiplication and division.
1, addition: the sum of two or more numbers is called addition. For example: 3+5=8.
2. subtraction: knowing the sum of two numbers, find out what these two numbers are. Subtraction is the inverse of addition. For example: 8-3=5.
3. Multiplication: The simple operation of finding the sum of several identical addends is called multiplication. For example: 3×4= 12 (pronounced: three times four equals twelve).
4. Division: The operation of finding the product of two factors and one of them is called division. For example: 12÷3=4 (pronunciation: twelve divided by three equals four).
When parentheses appear in four operations, the operation in parentheses takes precedence. For example: 2+(3- 1)×2=8, first calculate 3- 1=2 in brackets, then calculate the multiplication outside brackets, and finally calculate the addition. I hope the above information is helpful to you. If you have more questions about the fourth grade mathematics in primary school, you can ask your teacher or classmates.
Other related
Four operations are simple and basic mathematical operations, that is, four operations of addition, subtraction, multiplication and division. Four operations are the important content of primary school mathematics and the basis of learning other related knowledge.
Comprehensive formula
Comprehensive formula refers to the formula with addition, subtraction, multiplication and division at the same time, but at least one level (with two symbols) should pay attention to the comprehensive formula (four operations):
1. If there is only addition and subtraction or only multiplication and division, it is calculated from left to right. For example, 2+ 1- 1=2, first calculate the number of 2+ 1, and then subtract 1 from the number of 2+ 1.
2. If primary operation and secondary operation exist at the same time, the secondary operation is calculated first.
3. If there are primary, secondary and tertiary operations (i.e. power, root and logarithm operations) at the same time, first calculate the tertiary operation, and then calculate the other two levels.
4. If there are brackets, count the numbers in brackets first (no matter what level, count first).
5. The third level should be counted in brackets, and then the second and first levels should be counted.
6. If a number is divided by the sum or difference of two numbers, you can't divide the number by these two numbers and add or subtract them. For example:10 ÷ 5+10 ÷ 2 ≠10 ÷ (5+2).