What is the greatest common factor of 54 and 36?

It is ##18##

Because

##3*18 = 54## ##2*18 = 36##

Also

The factors of 54: ##1, 2, 3, 6, 9, 18, 27, 54 -1, -2, -3, -6, -9, -18, -27, -54 ##

The factors of 36: ##1, 2, 3, 4, 6, 9, 12, 18, 36 -1, -2, -3, -4, -6, -9, -12, -18, -36 ##

The of 54 and 36 = 18