3+2=5

5*6=30

Which formula can be used instead of 5 in the second formula? Change it to 3+2.

This 5 should be worked out first, so it should be put in brackets to indicate that it should be worked out first.

(3+2)*6=5*6=30

You can also use life experience to guide children.

Xiaohong bought three books and Xiaoming bought five books. How many books did they buy altogether? 3+2=5 (Ben).

6 yuan, how much did a book cost? 5*6=30 (yuan)

Want a * * *, how much is it? What should be counted first? The amount of money bought by two people is 3+2=5.

Therefore, 5 in the second formula can be represented by 3+2, because it must be put in brackets before it can be calculated.

(3+2)*6=30 (yuan).

Introduction to addition

Addition (usually indicated by the plus sign "+") is one of the four basic arithmetic operations, and the others are subtraction, multiplication and division. For example, in the picture below, * * * has a combination of three apples and two apples, and * * * counts as five apples. This observation is equivalent to the mathematical expression "3+2 = 5", that is, "3 plus 2 equals 5".

In addition to calculating fruits, you can also calculate other physical objects. Using system generalization, addition can also be defined on more abstract quantities, such as integers, rational numbers, real numbers and complex numbers, and other abstract objects, such as vectors and matrices.