What is the greatest common factor of 24 36 60?

Factors for 60 are: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60

Factors for 36 are: 1, 2, 3, 4, 6, 9, 12, 18, 36

Factors for 24 are: 1, 2, 3, 4, 6, 8, 12, 24

Greatest Common Factor is: 12

Alternative method using prime factors:

Factorise each number into its prime factors in power format. Greatest common factor is obtained by multiplying the common primes (in all the factorisations) to their lowest power (across the factorisations) together:

24 = 2^3 x 3

36 = 2^2 x 3^2

60 = 2^2 x 3 x 5

Prime 2 occurs in all factorisations, it is a common prime; lowest power is 2^2

Prime 3 occurs in all factorisations, it is a common prime; lowest power is 3 (= 3^1)

Prime 5 only occurs in the factorisation of 60, it is not a common prime.

greatest common factor = 2^2 x 3 = 12