The integer multiplication method can be checked using the cross line checker, and its principle 10

The following explanation, anyway, I didn't understand, the arithmetic of the cross line calculation! ~

Multiplication is generally calculated by swapping positions. It is also possible to use division.

Solution: Multiplication calculations are checked by division, edition.

For example: rights. 15x16=240

Check: 240 16 = 15

Or: 240 15 = 16

So the multiplication calculation is correct.

For the two-digit multiplication check, the positions of the two multipliers should be swapped and multiplied again. A multiplier is a multiplication of a single number, which is checked by division.

1.Integer addition calculation method:

The same digit pair is self-aligned, starting from the lowest digit, which digit adds up to ten, and the previous digit is advanced by one. 2.Integer subtraction calculation rules:

The same digits are aligned, and the number on which digit is not enough to subtract from the lower digit is retracted from its previous digit to make ten, and the number on the base is merged together, and then subtracted. 3.Integer multiplication calculation rules:

First, multiply the number on each digit of another factor by the number on each digit of another factor, multiply the number on which digit of the factor is used, align which digit at the end of the multiplied number, and then add up the numbers obtained by each multiplication. 4.Integer division calculation rules:

Divide by the high position of the dividend, the divisor is a few digits, and look at the first few digits of the dividend; If it is not enough to divide, look at one more digit, and divide to which digit of the dividend, and the quotient will be written on which digit. If one of them is not enough to quotient 1, it must be made up"0"Placeholding. The remainder of each division should be less than the divisor.

1.After calculating the number, divide the number by the multiplier to see that the equivalent is not equal to another multiplier.

2.Turn the multiplier upside down.

Learn to help.

Just test it by division and see if it's feasible.

Multiplication requires division.

For example: 12 16, the vertical calculation is as follows:

When calculating, divide 192 by 12, or 192 by 16 to see if the quotient is another factor.

1) 192 divided by 16, if the quotient is 12, it means that the operation is correct. Otherwise, the calculation is incorrect.

2) 192 divided by 12, if the quotient is 16, it means that the operation is correct. Otherwise, the calculation is incorrect.

Multiplication check:

1. Swap the positions of the two multipliers and multiply them again.

2. Divide the resulting product by one of the multipliers.

Multiplication can be checked using the following two visits:

1. The position of the two factors is recalculated once;

2. Divide the product by one of the factors to see if it is equal to the other.

If you agree with my answer, please adopt it in time, (click the [satisfactory answer] icon above my answer) Your adoption is my motivation to move forward! Your adoption will also bring you wealth value.

If you don't understand, you can ask until you understand the question!

If you have any new questions, please ask me for help, (but don't ask here) it is not easy to answer the questions, please understand......

Generally, only fractional equations have a calculation process, and integers are not needed.

Take a simple example: 5 8 = 40

Check: 40 8 = 5

The same method as integer multiplication, using division (dividing the product by one of the factors); Or use multiplication (swapping the positions of two factors).

Bring in the resulting product and do the divisor to see if it matches.

As with integer multiplication, the calculation is checked by division. Pay attention to the decimal place, though.

What is a discarded nine.

The remainder of a number divided by 9 is called discarding the number of nine. For example, 84 9 = 9 ......The number of discarded nines of 3,84 is 3.

We can add up a number, each digit, and continue to add until the result is a single number (if it is 9 and then subtract 9 it is 0), such as 8+4=.

In the exam, the results of the four operations of calculation (especially integers and decimals), if you go to the test, you always feel that the time cost is too great.

A method of using the property of the remainder obtained by dividing by 9 to test the results of the four operations is called the "discarded 9 test algorithm".

Using this method to check, we must first find out the "discarded 9 number" of a number, that is, the numbers on each digit of a number are added, if the sum is greater than 9 or equal to 9, 9 should be subtracted, until the remaining number is less than 9, we call this number the "discarded 9 number" of the original number.

In the application, you can directly cross out the numbers with a value of 9 or add up several numbers to get 9, and then add the remaining numbers to get a number less than 9, which is the discarded 9 number of the original number.

How to check decimal division:

Quotient divisor = dividend (generic).

Dividend quotient = divisor.

For example, 15 3 = 5 checks. It is whether multiplying the quotient by the divisor is equal to the dividend. The result of the check is 3 5 = 15, or 15 5 = 3.

After the problem is calculated, it is calculated again through the inverse operation (such as addition for subtraction and multiplication for division) to check whether the results of the previous operation are correct.

As with integer division, there are two main ways to check whether the decimal division is correct:

1. Use multiplication to check, that is, use the quotient divisor to compare with the dividend, if it is equal, it is correct, if it is not equal, it is not necessarily correct';

2. Use division to check, that is, use the dividend quotient to compare with the divisor, if it is equal, it is correct, if it is not equal, it is not necessarily correct'.

Multiply the quotient by divisor equals the dividend.

Division can be checked with multiplication.

Quotient divisor = dividend.

620 30 Vertical state calculation method and test the leakage trace sensitive return to the branch calculation.

If you want to check whether this number is correct, you can check it.

There are many ways to check the design. 1.You can swap the positions of the two multipliers and multiply them again to see if the numbers obtained twice are the same (for example, you can use multiplication to see if it is equal to ,); 2.

You can divide the product of multiplication by one factor to see if it is equal to another factor (e.g., this problem can be divided by to see if it is equal to; 3.You can also use the discarded nine-check algorithm, the discarded 11-check algorithm, the abandonment 99-check algorithm, the abandonment 101 test algorithm, etc.