Question 851233
Trucker A leaves Boston on the 1st day, the 31st day, the 61st day, the 91st day, the 121st day (etc -- just keep adding 30 days for start times)
Trucker B leaves Boston on the 1st day, the 9th day, the 17th day, the 26th day, the 35th day, the 42nd day, the 49th day, the 56th day, the 64th day, etc.  Multiples of 8 (+1)
.
Mathematically, what you're looking for is an intersection between multiples of 30 and multiples of 8 (and then you'll add 1 for the first day).
30,60,91,120,150,180...
8,16,24,32,40,48,56,64,72,80,88,96,104,112,120,128,136,..
What is the FIRST common number? 120
Add the first day.  They'll leave Boston together on the 1st day and again on the 121st day.



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