The number 33 bus arrives at the corner of Coldspring and Hillen every 15 minutes. The number 40 bus arrives at the same corner every 46 minutes. If both buses leave the corner at 9:08 am, when is the next time the buses arrive at the corner at the same time?
#33: 15 minutes, factors=5*3
#40: 46 minutes, factors=2*23
There are no common factors.
LCM : 3*5*2*23= 690
So it would be 690 minutes later (11 hours and 30 minutes) that the two buses arrive at the same corner at the same time.