4 9 4 9 5 6 1 2 How to do simple calculations?

It is directly 4 9 times (1-5 6) + 1 2 = 4 9 times 1 6 + 1 2 = 2 27 + 1 2 = 4 54 + 27 54 = 31 54.

The simple answer to 4 9-4 9 5 6+1 2 is as follows:

4 9 a 4 9x5 6 ten 1 2

ii. 4 9x (1a, 5, 6) x. 1, 2

II. 4, 9, 1, 6, X. 3, 6

ii. 1 6x (4 9 x. 3).

ii. 1 6x (4 9 x. 27 9).

II 1 6x31 9

II 31-54

Conform to the associative law of multiplication hope it will be helpful to you

Multiplicative associative law....

Equation 47 (54+47-1)=4700, first change like this....

And then calculate....

This problem lacks operator symbols and cannot be calculated;

Extract the common factor 47 and calculate it.

For this question, you can first count the inside of the parentheses, then count the inside of the middle brackets, and finally count the outside of the brackets.

It's not a simple math 340 (64-47) 5.

64 minus 47 equals 17

17 times 5 equals 85

340 divided by 85 equals 4

=340/(17x5)

The simple operation of this equation is to combine the points 340 and 17, or 34 and 17.

The formulas for the point 34 17 are listed below.

340/(17x5)

34x10)/(17x5)

34/17)x(10/5)= 2x2

There is no easy algorithm for this problem, it can only be calculated in order!

Normal calculations are simple. Count the inside of the brackets first, and then count the middle brackets, and you can calculate what easier calculations are needed.

The simple calculation of this question is: 31*52 47+52*16 47=(31*52+52*16) 47=[52(31+16)] 47=52*47 47=52.

1. Symbolic moving method: When a calculation problem only has the same level of operation (only multiplication and division or only addition and subtraction) and no parentheses, we can "move with symbols".

2. Union of the law.

1) Bracketed method.

When adding parentheses to addition and subtraction operations, the parentheses are preceded by a plus sign, the parentheses are unchanged, the parentheses are preceded by a minus sign, and the parentheses are changed.

When adding parentheses to the multiplication and division operation, the parentheses are preceded by the multiplication sign, the parentheses are unchanged, the parentheses are preceded by the division sign, and the parentheses are changed by the sign.

2) De-bracket method.

When removing parentheses in addition and subtraction operations, the parentheses are preceded by the plus sign, the parentheses are removed and the parentheses are unchanged, and the parentheses are preceded by the minus sign, and the parentheses are removed to change the sign (the original addition in the parentheses is now to be subtracted; It used to be minus, but now it is going to be added).

When removing parentheses in the multiplication and division operation, the parentheses are preceded by the multiplication sign, the parentheses are removed and the invariant sign is removed, and the division sign is preceded by the parentheses. It used to be dividing, but now it's going to be multiplied).

3. Multiplication and distributive law.

Distribution: In parentheses is an addition or subtraction operation, multiplying with another number, pay attention to the distribution.

Extract common factor: Pay attention to the extraction of the same factor.

Pay attention to the construction so that the equation satisfies the conditions of the multiplicative distributive property.

4. Rounding method: When you see the name, you know the meaning of this method. When using this method, you need to pay attention to observation and find patterns. Also pay attention to repay, there is borrowing and repaying, and it is not difficult to borrow again.

5. Splitting method: The splitting method is to facilitate the calculation of splitting a number into several numbers. This requires mastering some "good friends" such as: 2 and 5, 4 and 5, 4 and 25, 8 and 125, etc. Splitting is also careful not to change the size of the number.