Trả lời:
a, 12 = 22.3
90 = 2.32.5
150 = 2.3.52
=> BCNN (12,90,150) = 22.32.52 = 900
b, 24 = 23.3
30 = 2.3.5
=> BCNN (24,30) = 23.3.5 = 120
c, 3 = 3
7 = 7
8 = 23
=> BCNN (3,7,8) = 23.3.7 = 168
d, 12 = 22.3
16 = 24
48 = 24.3
=> BCNN (12,16,48) = 24.3 = 48