Since 18 is a factor of 180, all of its factors are common.
A factor is a divisor - a number that will evenly divide into another number. The greatest common factor of two or more numbers is the largest factor that both numbers have in common. One way to determine the common factors and greatest common factor is to find all the factors of the numbers and compare them. The factors of 28 are 1, 2, 4, 7, 14, and 28. The factors of 180 are 1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18, 20, 30, 36, 45, 60, 90, and 180. The common factors are 1, 2, and 4. Therefore, the greatest common factor is 4.
The common factors of 6 and 180 are: 1, 2, 3, and 6
The common factors of 10 and 180 are: 1, 2, 5, and 10
The common factors of 28 and 84 are 1,2,4,7,14 and 28
The common factors of 28 and 84 are 1,2,4,7,14 and 28.
The common factors of 54 and 180 are: 1, 2, 3, 6, 9, and 18
The common factors of 180 and 225 are 1, 3, 5, 9, 15 and 45.
The factors of 28 are 1,2,4,7,14 and 28. "Common" means "same for both". For these factors to be common, they need to be compared to the factors of another number.
The common factors are: 1, 2, 4
Common factors of 260 and 180 are: 1, 2, 4, 5, 10, and 20.
The common factors of 28 and 50 are 1 and 2