jassims aunt visits every five days. Janusan uncle visits every 3 days. the last time the aunt and uncle both visited on the same day was november 3rd. whats is the next day they will both visit on the same day

So their visits coincide every 15 days, the LCM of 5 and 3.

I will let you do the counting of 15 days from Nov 3

the LCM (least common multiple) of 3 and 5 is 15 ... so, 15 days