Răspuns:
Se iau toți factorii primi comuni, la puterile cele mai mici.
a) cmmdc (24, 36) = 2²× 3 = 12
b) cmmdc (28, 42) = 2 × 7 = 14
c) cmmdc (30, 45) = 3× 5 = 15
d) cmmdc (36, 54) = 2 ×3² = 18
e) cmmdc (60, 48) = 2² × 3 = 12
f) cmmdc (48, 72) = 2³ × 3 = 24
g) cmmdc (75, 60) = 3 ×5 = 15
h) cmmdc (72, 90) = 2 × 3²= 18
i) cmmdc (80, 120) = 2³ * 5 = 40
j) 90 = 2 * 3² * 5 ;135 = 3³ * 5 ; cmmdc (90, 135) = 3² × 5 = 45
k) 144 = 2²×2²× 3² ;96 = 2²×2³× 3 ; cmmdc (144, 96) = 2²×2² × 3 = 48
l) 72 = 2³ × 3² ; 180 = 2² × 3² × 5 ; cmmdc (72, 180) = 2² × 3² = 36
72;180