Răspuns :

54=2 * 3³
63=3² * 7
72=2³ *3²

(54;63;72)= 3²=9
54 = 2 * 3 * 3 * 3
63 = 3 * 3 * 7
72 = 2 * 2 * 2 * 3 * 3
__________________________
C.M.M.D.C = 3 * 3 = 9