The common factors of 8 and 12 can list all the factors of 8 and 12 respectively, and then look.

Factor of 8: 1, 2, 4, 8.

12 factors: 1, 2, 3, 4, 6, 12.

The common factor of 8 and 12 is 1, 2,4, of which the largest is 4.

You can also find the factor of 8 first, and then find the factor of 12 from the factor of 8.

Factor of 8: 1, 2, 4, 8.

Where 1, 2,4 is also a factor of 12.

The common factor of 8 and 12 is 1, 2,4, of which the largest is 4.

2, toss division (Euclid algorithm)

Dividing by division means dividing the larger number of two numbers by the smaller number first. If there is a remainder, continue to divide the smaller number by the remainder, and so on until the remainder is 0, then the final divisor is the greatest common factor of two numbers.

Extended data

Difference between phase division and phase subtraction

(1) are all methods to find the greatest common factor. Division is the main method in calculation, and subtraction is the main method in subtraction. The calculation times of division are relatively few, especially when the size of two numbers is quite different.

(2) From the form of the result, the result of division is obtained when the remainder of division is 0, while subtraction is obtained when subtraction equals difference.

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