Se iau toți factorii primi comuni, la puterile cele mai mici
90 = 2 × 3² × 5
168 = 2³× 3 × 7
c.m.m.d.c. (90, 168)=2×3=6
100.280 si 980
100 280 = 2³ × 5 × 109
980 = 2² ×5 × 7²
cmmdc (100 280, 980) = 22 × 5 = 20
875 si 500
875 = 5³ × 7
500 = 2² × 5³
cmmdc (875, 500) = 5³ = 125
[tex]16= 2^{4} \\ 48=2^{4}*3 \\64=2^{6} \\ 72=2^{3}*3^{2}\\ cmmdc (16,48,64 , 72 )=2^{3}[/tex]
