Jawabanmu

2014-08-31T10:41:32+07:00
2014-08-31T11:15:48+07:00
3=3,6,9,12,15,.....
4=4,8,12,16,....
5=5,10,15,20,.....
7=7,14,21,28,......
bisa dibagi keempatnya = 3x4x5x7
                                   = 420