greatest common factor=gcf least common multule=lcm with 12 and 16 factors of 12=2 times 2 times 3 factors of 16=2 times 2 times 2 times 2 greates common factor is 2 times 2=4 least common multiule means all factors combined minus repeats or 2 times 2 times 2 times 2 times 3=48