Вариант№1
НОК (6,12)=12
6║6, 12.
12║12.
НОК(40,8)=40.
40║40.
8║8, 16, 24, 32, 40.
НОК(51,17)=51.
51║51.
17║17, 34, 51.
НОК(33,3)=33.
33║33.
3║3,6,9, 12, 15, 18, 21, 24, 27, 30, 33.
НОК(34,2)=34.
34║34.
2║2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34.
НОК(16,48)=48.
16║16, 32, 48.
48║48.
Готово!
Вариант№2
6║2 12║2
3║3 6 ║2
1║1 3 ║3
1║1
НОК(6,12)=2*3*2=12.